Daily Prelims MCQs - Sci-Tech, Environment and Geography - 5th August 2025

Welcome to today’s handpicked set of Multiple-Choice Questions (MCQs) from the Science, Technology, Environment and Geography — crafted specially for the UPSC Prelims! These questions aren’t just a quiz — they’re a smart way to see how current affairs connect with core concepts, just like UPSC asks in the exam.

Each question is based on recent news and backed by clear explanations to help you build strong links between dynamic events and static knowledge.

Today’s topics include:

Click Here to read the Monthly Current Affairs Pointers (CAP).

QUESTION 1

With respect to the Pralay missile, consider the following statements:

1. It is a domestically developed solid-fuel quasi-ballistic missile.

2. This missile can carry various types of warheads designed for different target profiles.

3. The inaugural test of the Pralay missile took place in 2024.

How many of these statements are correct?

(a) Only one

(b) Only two

(c) All three(d) None

Answer (b)

Explanation:

The Defence Research and Development Organisation (DRDO) successfully conducted two back-to-back flight tests of the Pralay missile from Dr. APJ Abdul Kalam Island located off the Odisha coast. These tests were user evaluation trials aimed at verifying the missile’s full range capabilities, including both its maximum and minimum distances. The missile followed the planned flight path precisely and achieved its target with exceptional accuracy, fulfilling all the intended objectives.

The Pralay missile is an indigenously developed system using solid propellant technology and follows a quasi-ballistic trajectory. It incorporates advanced guidance and navigation systems to maintain high precision during flight. Additionally, it is designed to carry multiple warhead types to engage diverse targets effectively. Thus, Statements 1 and 2 are correct.

However, Statement 3 is incorrect because the first successful test of the Pralay missile occurred in December 2021, not 2024. The missile, which derives its name from the Sanskrit word meaning "widespread destruction," is expected to be equipped with conventional warheads and integrated into the Indian Army’s artillery units.

Key Terms:

• Solid Propellant: A type of rocket fuel that is in solid form, providing advantages such as ease of storage and quicker launch readiness compared to liquid fuels.

• Quasi-Ballistic Missile: A missile that follows a trajectory similar to a ballistic missile but can maneuver during flight to avoid interception or improve accuracy.

• Guidance and Navigation Systems: Technologies that help the missile determine its path and adjust in real-time to correctly hit the target.

QUESTION 2

Regarding the Synthetic Aperture Radars (SARs) onboard the NISAR (NASA-ISRO Synthetic Aperture Radar) satellite, consider the following statements:

1. Both L-band and S-band radars are capable of penetrating clouds, smoke, rain, or fog, allowing them to capture clear images of Earth in any weather and during both day and night.

2. The S-band SAR employs microwaves with longer wavelengths, enabling deeper penetration through tree canopy, vegetation, as well as sand or ice.

3. The L-band SAR operates with shorter wavelengths, limiting its penetration depth, but it is effective in imaging large-scale features such as agricultural fields and water bodies.

How many of the above statements are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Answer (a)

Explanation:

NISAR, a joint project between NASA and ISRO, distinguishes itself by carrying two distinct SAR instruments — one operating in the L-band and the other in the S-band frequency range. These two radars work together to simultaneously capture complementary data of the same geographic area, offering an unprecedented level of detail in Earth observation.

• Both L-band and S-band Synthetic Aperture Radars (SARs) can penetrate through atmospheric obstacles such as clouds, smoke, rain, and fog. This capability allows them to capture clear images regardless of weather conditions and time of day, providing continuous monitoring. This statement is correct.

  • SAR (Synthetic Aperture Radar) is a remote sensing technology that uses radar signals to produce high-resolution images of Earth's surface, capable of operating through clouds and in darkness.

• Contrary to the statement, the S-band SAR uses microwaves with shorter wavelengths compared to the L-band. Due to this, the S-band has limited penetration capability through dense vegetation or ground surfaces but is useful for monitoring larger features such as crop fields and water bodies. Hence, this statement is incorrect.

  • Wavelength refers to the distance between two successive peaks of a wave; longer wavelengths generally penetrate deeper into materials.

• The L-band SAR uses longer wavelengths, which allow it to penetrate deeper into dense vegetation, sand, or ice. This makes it effective for detailed mapping beneath forest canopies, including measuring biomass for carbon stock estimation. The statement incorrectly describes L-band SAR as having a shorter wavelength and only capturing large features, so it is incorrect.

  • Biomass refers to the total mass of living plants in a given area, important for understanding carbon storage.

QUESTION 3

Consider the following pairs linking pollutants to their primary sources:

1. PM2.5 – Mainly originates from vehicle exhaust and emissions from thermal power stations.

2. Nitrogen dioxide (NO₂) – Generated chiefly due to the combustion of fossil fuels by vehicles, thermal power plants, and various industries.

3. Soot (Black Carbon) – Emitted from vehicle exhausts and the burning of wood.

How many of these pairs correctly match the pollutant with its source?

(a) Only one pair

(b) Only two pairs

(c) All three pairs

(d) None of the above

Answer (c)

Explanation:

A comprehensive study conducted by researchers at Cambridge University, published in The Lancet Planetary Health (July 24), analyzed data from over 29 million individuals exposed to air pollution for at least one year, across 51 studies. This extensive research establishes a clear link between long-term exposure to common air pollutants and an increased risk of developing dementia.

• PM2.5 (Particulate Matter 2.5 micrometers or smaller): These tiny particles mainly come from vehicle emissions and thermal power plants. They are small enough to penetrate deep into the lungs and even enter the bloodstream. The study shows that an increase of 10 micrograms per cubic meter (µg/m³) in PM2.5 concentration correlates with a 17% rise in the risk of dementia.

  • PM2.5 refers to particulate matter with a diameter less than or equal to 2.5 micrometers, which is approximately 30 times smaller than the width of a human hair.

• Nitrogen dioxide (NO₂): Produced largely from burning fossil fuels by vehicles, power plants, and industries. The study found that every 10 μg/m³ increase in NO₂ exposure is associated with a 3% increase in dementia risk.

  • NO₂ is a harmful gas that contributes to respiratory problems and forms smog and acid rain.

• Soot (also called Black Carbon): Originates mainly from vehicle exhaust and wood combustion. Black carbon is a component of PM2.5 and contributes to air pollution and climate change. The study linked every 1 μg/m³ increase in soot to a 13% increase in dementia risk. Although the Central Pollution Control Board (CPCB) does not specifically monitor black carbon separately from PM2.5, its significance is well-recognized.

  • Soot or black carbon consists of fine particulate matter produced by incomplete combustion of fossil fuels and biomass.

QUESTION 4

In the context of earthquakes, the term “hypocenter” specifically refers to:

(a) The point beneath the Earth’s surface where the earthquake originates

(b) The surface location where the Earth’s crust fractures during an earthquake

(c) The position from which a seismograph records the earthquake’s intensity

(d) The area adjacent to a region prone to seismic activity

Answer (a)

Definitions of Key Terms:

• Hypocenter: The exact location inside the Earth where the rupture begins and the earthquake originates. It is also known as the focus of the earthquake.

• Seismograph: An instrument that detects and records the vibrations caused by seismic waves during an earthquake.

• Elastic Strain Energy: The stored energy accumulated when rocks are deformed under stress but have not yet broken. When released suddenly, it causes seismic waves.

Explanation:

An earthquake is caused by the sudden release of accumulated elastic strain energy due to the movement of tectonic plates—massive slabs of Earth’s crust that continually shift and interact. These plates do not slide smoothly because their edges are rough and become locked, accumulating stress over time.

When the stress exceeds the strength of the rocks at the fault (the fracture zone between plates), the rocks break or slip abruptly. This sudden movement releases energy that travels as seismic waves, shaking the ground.

The point within the Earth where this rupture initiates is called the hypocenter (or focus). This is a subsurface location beneath the Earth’s crust. The point directly above this, on the surface of the Earth, is known as the epicenter.

For example, a powerful earthquake measuring 8.8 on the Richter scale struck near Russia’s Kamchatka Peninsula. This event triggered tsunami waves reaching heights of up to 16 feet, which traveled thousands of miles to impact distant locations such as the Hawaiian Islands and the northern coast of California in the United States.

According to the United States Geological Survey (USGS), the hypocenter is the exact location underground where an earthquake begins.

QUESTION 5

Regarding ham radio, consider the following statements:

1. It is primarily used for learning and educational activities.

2. Communication is possible only between two licensed amateur radio operators.

3. In India, individuals younger than 21 years are prohibited from operating a ham radio.

Which of these statements is/are correct?

(a) 1 and 2 only

(b) 2 only

(c) 2 and 3 only

(d) 1, 2, and 3

Answer (a)

Explanation:

Ham radio, also known as amateur radio, is a licensed communication service where enthusiasts use designated radio frequencies to exchange information. It serves several purposes including education, public service, and emergency communications.

For example, Shubhanshu Shukla, an Indian astronaut aboard the International Space Station (ISS), utilized ham radio to connect directly with school students in India, showcasing its educational use. This confirms that ham radio is widely employed for learning and knowledge dissemination.

Communication via ham radio requires that both parties hold valid licenses, ensuring authorized and regulated operation. Operators use a combination of a transceiver (a device that can both transmit and receive radio signals) and antennas tuned to specific frequencies to establish contact. This means only licensed amateurs can legally communicate through these channels.

Contrary to some misconceptions, in India, the minimum age for obtaining a ham radio license is 12 years, not 21. The Ministry of Electronics and Information Technology (MeitY) oversees the issuance of these licenses. Thus, the restriction mentioned in statement 3 is incorrect.

Historically, ham radio has been significant in space communication as well: in 1983, it was first employed on a space shuttle for communication between astronauts and Earth. The ISS continues this tradition with its onboard Amateur Radio on the International Space Station (ARISS) system, promoting educational interactions between astronauts and students worldwide. This initiative is supported by amateur radio societies and space agencies across several countries.

QUESTION 6

Regarding the Indian Space Research Organisation (ISRO), analyze the following statements:

1. ISRO was established in 1969 as a successor to the Indian National Committee for Space Research (INCOSPAR).

2. It operates as the primary space agency under the Department of Space (DoS), which was constituted in 1972.

3. ISRO’s primary responsibilities include the development of satellites, launch vehicles, and the utilization of space technology for national development.

4. The organisation functions independently under the Ministry of Science & Technology.

Which of the above statements are correct?

(a) 1 and 4 only

(b) 1, 2, and 3 only

(c) 2 and 4 only

(d) All the above

Answer (b)

Explanation:

The Indian Space Research Organisation (ISRO) is India's premier space agency, dedicated to advancing science, technology, and the peaceful use of outer space for the benefit of India and humanity. Initially, the space program was managed by the Indian National Committee for Space Research (INCOSPAR), which was established in 1962 under the guidance of Dr. Vikram Sarabhai, regarded as the father of the Indian space program.

ISRO was officially created on 15 August 1969, taking over from INCOSPAR with a broader mandate to develop and exploit space technology. Subsequently, in 1972, the Government of India formed the Department of Space (DoS) to oversee the country's space activities, and ISRO became a major component under this department.

ISRO is entrusted with designing and developing satellite launch vehicles such as the PSLV (Polar Satellite Launch Vehicle) and GSLV (Geosynchronous Satellite Launch Vehicle), which serve to deploy satellites into precise orbits for communication, weather forecasting, and other applications. The organisation’s core mission includes harnessing space technology for societal benefits like telecommunication, education, and disaster management.

Contrary to some beliefs, ISRO operates under the Department of Space, which in turn reports directly to the Prime Minister of India, and not under the Ministry of Science & Technology. Hence, ISRO is not autonomous under that ministry.

• INCOSPAR (Indian National Committee for Space Research): The precursor committee to ISRO, set up in 1962 to promote space research activities in India.

• Department of Space (DoS): Established in 1972, this is the government department responsible for space activities and the administrative control of ISRO.

• PSLV (Polar Satellite Launch Vehicle): A reliable Indian rocket that places satellites into polar orbits, widely used for launching satellites.

• GSLV (Geosynchronous Satellite Launch Vehicle): A heavier Indian launch vehicle designed to place satellites into geosynchronous orbits (orbits where satellites remain fixed over a point on the Earth).

QUESTION 7

What are Population III stars?

(a) The earliest generation of stars formed in the universe

(b) The stars formed recently in the universe

(c) The smallest, faint, and long-lasting stars

(d) None of the above

Answer (a)

Explanation:

Population III stars refer to the very first stars that emerged in the cosmos. Unlike the stars we observe today, these primordial stars were made almost entirely of hydrogen and helium — the two simplest and lightest elements created during the Big Bang. Because they formed from this pristine gas (meaning untouched by heavier elements), these stars were exceptionally massive, some possibly reaching hundreds of times the mass of our Sun. Their enormous mass caused them to burn extremely hot and shine intensely, but also to have very short lifespans.

When these stars ended their lives, they exploded as powerful supernovae, dispersing heavier elements (such as carbon, oxygen, and iron) into space. This cosmic "pollution" with heavier elements, called metals in astronomy, paved the way for the formation of later generations of stars, planets, and ultimately, the conditions necessary for life as we know it.

QUESTION 8

With reference to the cosmic phenomenon known as reionization, consider the following statements:

1. Reionization is a crucial event in the early history of the universe, as it provides one of the rare ways to indirectly observe the very first generation of stars.

2. Researchers have recently pinpointed the exact timeline of when the first stars ignited and when the reionization process commenced.

Which of the statements above is/are correct?

(a) Only 1

(b) Only 2

(c) Both 1 and 2

(d) Neither 1 nor 2

Answer (a)

Explanation:

According to NASA’s scientific research, the epoch of reionization marks a significant phase in the universe’s evolution, occurring roughly within the first billion years after the Big Bang. During this epoch, ultraviolet radiation emitted by the earliest massive stars had enough energy to ionize neutral hydrogen atoms, meaning these atoms were split into free protons and electrons. This ionization transformed the universe from being mostly filled with neutral hydrogen gas to one dominated by ionized hydrogen.

Reionization is fundamental because it indirectly reveals information about the universe’s first stars—stars which are otherwise challenging to observe directly due to their immense distance and faintness. However, scientists have not yet determined the precise timing of when these first stars formed or exactly when the reionization period began. Therefore, only the first statement is correct.

QUESTION 1

Concerning the Great Indian Bustard (GIB), evaluate the following assertions:

1. It serves as a crucial indicator species for the condition of grassland ecosystems.

2. It is currently listed as a Vulnerable species under the IUCN Red List.

3. A seven-member expert panel was constituted to formulate conservation strategies for this bird, aiming to reconcile its survival with the expansion of renewable energy infrastructure in its habitat zones.

4. The GIB’s population trend has shown a noticeable rise in recent years.

How many of these statements are correct?

(a) Only one

(b) Only two

(c) Only three

(d) All four

Answer (b)

Explanation:

Statement 1 is Correct:

The Great Indian Bustard is considered a key indicator species for grasslands.

• An indicator species is one whose presence, absence, or abundance reflects a specific environmental condition.

• In this case, the health and survival of GIBs signal the ecological well-being of grassland habitats, which are among the most neglected ecosystems in India.

Statement 2 is Incorrect:

The GIB is not classified as Vulnerable; it is Critically Endangered as per the IUCN Red List.

• The International Union for Conservation of Nature (IUCN) classifies species based on their extinction risk.

• Critically Endangered is the highest threat level before extinction in the wild, indicating that the species faces an extremely high risk of extinction.

Statement 3 is Correct:

A seven-member committee was indeed set up in March 2024 by the Supreme Court of India.

• The committee's purpose was to propose solutions for conserving the GIB, especially considering threats from overhead power transmission lines used in renewable energy projects (solar, wind) in Rajasthan and Gujarat, where the GIB still survives in small numbers.

• Among its proposals were creating dedicated green energy corridors, rerouting existing lines, and placing high-risk lines underground to prevent bird collisions.

Statement 4 is Incorrect:

Contrary to what is claimed, the population of the Great Indian Bustard has been declining, not increasing.

• According to data from the Rajasthan Forest Department, the population has dwindled from 700+ individuals decades ago to fewer than 150 today.

• The drop is mainly due to habitat loss, hunting, and collision with power lines, which are now a major cause of mortality.

QUESTION 2

Consider the following statements with reference to Kaziranga National Park:

1. Kaziranga Tiger Reserve has the highest tiger density in the world.

2. The first organized bird census focusing on grassland species was carried out in Kaziranga.

3. Kaziranga harbors the largest global population of the one-horned rhinoceros.

4. It was designated as a UNESCO World Heritage Site in the year 2021.

How many of the above statements are correct?

 (a) Only one

(b) Only two

(c) Only three

(d) All four

Answer (b)

Explanation:

Statement 1 is Incorrect:

Although Kaziranga Tiger Reserve (located in Assam) is renowned for its tiger population, it does not hold the highest tiger density globally.According to a comprehensive survey on tigers, Kaziranga reports a tiger density of 18.65 tigers per 100 square kilometers, which ranks it third in the world, not first.

Tiger Density refers to the number of tigers per 100 sq. km — an important metric in wildlife conservation to assess habitat quality and tiger survival prospects.

Statement 2 is Correct:

Kaziranga is notable for hosting the first-ever bird census dedicated to grassland species in India.This survey aimed to assess the diversity and abundance of birds dependent on grassland ecosystems — habitats that are often under-documented but crucial for certain endangered species.

Grassland Birds are bird species that rely heavily on open, grassy habitats for nesting, feeding, and breeding. These include birds like the Bengal Florican, which is critically endangered.

Statement 3 is Correct:

Kaziranga is world-famous for having the largest population of the one-horned rhinoceros (Rhinoceros unicornis).Conservation efforts and habitat protection in the park have made it a global stronghold for this species, which is listed as Vulnerable on the IUCN Red List.

The One-Horned Rhinoceros is native to the Indian subcontinent and is known for its thick, armor-like skin and single black horn. It once ranged from Pakistan to Myanmar but now survives mainly in northeastern India and parts of Nepal.

Statement 4 is Incorrect:

Kaziranga was recognized as a UNESCO World Heritage Site much earlier than 2021 — specifically in 1985, due to its rich biodiversity, unique ecosystem, and exceptional conservation value.

UNESCO World Heritage Site is a landmark or area recognized by the United Nations Educational, Scientific and Cultural Organization for having cultural, historical, scientific, or other forms of significance, and is legally protected by international treaties.

QUESTION 3

With reference to mercury and its environmental and health impacts, consider the following statements:

1. Exposure to mercury can lead to several serious disorders affecting the brain, skin, and cardiovascular system.

2. There are no instances of mercury contamination in India’s groundwater.

3. Mercury can originate from both natural events and industrial activities.

How many of the statements given above are correct?

 (a) Only one

(b) Only two

(c) All three

(d) None

Answer (b)

Explanation:

Statement 1 is correct:

• Mercury is recognized globally as one of the most hazardous heavy metals to human health.

• Even low levels of exposure—especially through consumption of contaminated water or seafood—can result in severe neurological (brain-related), dermatological (skin-related), and cardiovascular (heart-related) issues.

• Long-term or high-dose exposure may lead to developmental delays, cognitive impairments, and in some cases, even death.

Neurotoxicity: Mercury is a neurotoxin, meaning it disrupts the nervous system, particularly harmful to pregnant women and young children due to its effect on brain development.

Statement 2 is incorrect:

• While mercury contamination is not widespread across India, it has been detected at alarming levels in certain regions.

• According to studies, including one by the Central Pollution Control Board (CPCB):

  • Groundwater and surface water in states like Maharashtra, Gujarat, Haryana, and Odisha have shown dangerous mercury concentrations.

  • Industrial belts—particularly those near leather tanneries, mining zones, and chemical industries—are hotspots for such contamination.

Just 1 gram of mercury from a broken thermometer can render 20 acres of water unfit for fishing due to bioaccumulation in aquatic organisms.

Statement 3 is correct:

• Mercury is released both naturally and through anthropogenic (human-made) processes:

  • Natural sources include volcanic eruptions, forest fires, and weathering of rocks.

  • Industrial sources include coal-fired power plants, waste incineration, mining, and manufacturing (especially of batteries, thermometers, and fluorescent lamps).

QUESTION 4

The under-construction Zojila Tunnel in the Union Territory of Jammu and Kashmir is designed to provide all-weather connectivity between which of the following locations?

(a) Jammu and Srinagar

(b) Keylong and Leh

(c) Jammu and Leh

(d) Srinagar and Ladakh

Answer (d)

Explanation:

• The Zojila Tunnel is a strategically significant infrastructure project situated in the Himalayan region of Jammu and Kashmir. Once completed, it will offer year-round, weather-independent road access between Srinagar (summer capital of Jammu and Kashmir) and Ladakh (a high-altitude, landlocked region bordering China and Pakistan).

Why is the Tunnel Important?

• The tunnel is being built at a lofty elevation of approximately 11,578 feet (3,528 meters), in one of the most challenging and avalanche-prone mountain passes in India — the Zojila Pass.

• Currently, this region remains cut off for about 5–6 months every winter due to heavy snowfall and landslides, severely impacting both civilian life and military logistics in Ladakh.

Zojila Pass: A high-altitude mountain pass in the Himalayas, connecting the Kashmir Valley to Ladakh. It becomes impassable in winters, disrupting strategic mobility and supply chains.

Key Features of the Zojila Tunnel:

• Once finished, it will become:

  • India’s longest road tunnel

  • Asia’s longest bi-directional tunnel (a tunnel that supports traffic in both directions simultaneously)

QUESTION 5

Which among the following bird species are considered endemic to the Brahmaputra floodplain ecosystem?

1. Bengal Florican

2. Swamp Francolin

3. Bristled Grassbird

4. Slender-billed Babbler

Select the correct answer using the code below:

 (a) 1 and 2 only

(b) 2 and 3 only

(c) 2, 3 and 4

(d) 1, 2, 3 and 4

Answer (d)

Explanation:

• In a recent episode of Mann ki Baat, Prime Minister Narendra Modi drew attention to India’s first dedicated census of grassland birds conducted in Kaziranga National Park, Assam — a biodiversity hotspot located in the Brahmaputra floodplains.

• The effort was spearheaded by a PhD researcher, Chiranjib Bora, who was investigating the endangered Black-breasted Parrotbill. He received funding via an INSPIRE scholarship from the Department of Science and Technology, along with advanced acoustic monitoring tools to track elusive bird species.

What is Endemism?

A species is considered endemic when it is native to and exclusively found in a particular geographic region — in this case, the Brahmaputra floodplains. These species do not naturally occur elsewhere in the world.

Background of the Census:

• The field survey ran from March 18 to May 25 in 2023, involving collaboration among forest officials, scientists, and conservationists.

• The survey was focused specifically on grassland bird species — unlike wetland or forest birds, grassland birds are often small, camouflaged, and difficult to detect due to their habitat and behavior.

• The grassland ecosystem in this region is rapidly shrinking, putting these species at greater risk.

Targeted Endemic and Threatened Species:

The census focused on 10 grassland bird species that are either globally threatened or endemic to the Brahmaputra floodplains, including:

• Bengal Florican (Critically Endangered – IUCN Red List)

• Swamp Francolin

• Bristled Grassbird

• Slender-billed Babbler

• Plus others: Finn’s Weaver, Swamp Grass Babbler, Marsh Babbler, Indian Grassbird, Black-breasted Parrotbill, and Jerdon’s Babbler.

  • These species are restricted to specific riverine grassland habitats, especially along the Brahmaputra, and are rarely found outside this zone.

• The survey recorded 43 species of grassland birds in total.

• Among them:

  • 1 species was Critically Endangered

  • 2 species were classified as Endangered

  • 6 species were listed as Vulnerable, as per the IUCN Red List of Threatened Species.

    • IUCN Red List: A global inventory that classifies species based on their risk of extinction. Categories include: Least Concern, Vulnerable, Endangered, and Critically Endangered.

QUESTION 6

Regarding India’s first privately-run facility for heavy water upgradation, consider the following statements:

1. The test facility has been established by a private firm through a technology transfer arrangement from the Bhabha Atomic Research Centre (BARC).

2. It is equipped to produce and evaluate equipment like distillation columns, which are essential for purifying heavy water.

3. The core objective is to convert ordinary water (H₂O) into heavy water (D₂O) for use in nuclear reactors.

4. The facility is expected to significantly reduce the equipment validation timeline by one to two years.

Which of the statements given above are correct?

(a) 1 and 3 only

(b) 2 and 4 only

(c) 1, 2 and 4 only

(d) All of the above

Answer (c)

Explanation:

• Statement 1 is correct: A Mumbai-based private engineering company, TEMA India, has set up this test facility after receiving technology from BARC (Bhabha Atomic Research Centre). This initiative was formally launched under an order from NPCIL (Nuclear Power Corporation of India Limited).

  • Technology Transfer: This refers to the process where innovations, designs, or operational knowledge developed by one organization (in this case, BARC) are shared with another (TEMA India), enabling the latter to implement or manufacture using that technology.

• Statement 2 is correct: The facility is designed to manufacture and test crucial components—particularly distillation columns and modules—used in the upgradation (re-purification) of depleted heavy water (i.e., heavy water that has lost some of its deuterium concentration during use in reactors).

  • Distillation Columns: These are large vertical units used in chemical engineering to separate mixtures based on differences in boiling points. In this context, they help purify heavy water to restore its high deuterium concentration (typically ~99.9%).

• Statement 3 is incorrect: This facility does not produce heavy water (D₂O) from regular water (H₂O). Instead, it is focused on restoring the purity of already-used heavy water—which is essential in Pressurized Heavy Water Reactors (PHWRs) to sustain efficient nuclear fission.

  • Heavy Water (D₂O): Water where the hydrogen atoms are replaced with deuterium, a heavier isotope of hydrogen. It's used as a moderator and coolant in PHWRs to maintain neutron economy.The process of creating D₂O from H₂O is highly energy-intensive and is not the function of this facility.

• Statement 4 is correct: According to TEMA India, integrating equipment fabrication and testing under one roof can significantly reduce the overall project timeline—by 1 to 2 years, compared to the earlier model where BARC alone handled testing after manufacturing elsewhere. Previously, this full cycle could take 7–8 years.

QUESTION 7

Which of the following countries is not listed as a member of the ‘Mangrove Alliance for Climate’?

(a) India

(b) Japan

(c) United Kingdom

(d) United States of America

Answer (d)

Explanation:

• The Mangrove Alliance for Climate (MAC) is an international initiative aimed at protecting and restoring mangrove ecosystems across the world.

• It promotes the use of mangroves as a nature-based solution to combat climate change.

  • Nature-based solutions refer to sustainable strategies that involve protecting, restoring, or managing ecosystems to address societal challenges such as climate change, disaster risk, and biodiversity loss.

• The alliance was launched during COP27.

  • COP27 refers to the 27th Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC), held in Sharm el-Sheikh, Egypt, in 2022.

• The initiative is spearheaded by the United Arab Emirates (UAE) in collaboration with Indonesia.

• Countries like India, Japan, and the United Kingdom are among the listed members of the alliance.

• However, the United States of America (USA) is not a listed member of the Mangrove Alliance for Climate. Hence, statement (d) is the correct answer.

• Mangroves are coastal forests found in tropical and subtropical regions.

  • They act as carbon sinks, absorbing large amounts of carbon dioxide.

  • They also protect coastlines from erosion, storm surges, and rising sea levels.

• The MAC aims to scale up mangrove conservation efforts, raise awareness, and promote scientific research and policy coordination among member countries.

QUESTION 8

Consider the following statements regarding the Etalin Hydel Project:

1. It is a run-of-the-river project located in Arunachal Pradesh.

2. It is being built on the Subansiri and Lohit rivers.

3. The area where the project is proposed is part of a biodiversity hotspot that is home to rare and endangered species like the Mishmi takin, red panda, clouded leopard, snow leopard, and many bird species.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 1 and 3 only

(c) 2 and 3 only

(d) 1, 2 and 3

Answer (b)

Explanation:

• The Etalin Hydel Project is a hydroelectric power project proposed in the Dibang Valley of Arunachal Pradesh.

• It is designed as a run-of-the-river project.

  • A run-of-the-river project is a type of hydroelectric generation where little or no water storage is involved.

  • Unlike conventional dams, these projects typically do not require large reservoirs and instead use the natural flow of rivers.

• The project is being developed by the Etalin Hydro Electric Power Company Limited (EHEPCL).

  • This is a joint venture between Jindal Power Limited and the Government of Arunachal Pradesh.

• The project is not located on the Subansiri and Lohit rivers.

  • It is actually planned on two tributaries of the Dibang River — namely, the Dri River and the Talo (also called Tangon) River. Therefore, statement 2 is incorrect.

• The project will involve the construction of two concrete gravity dams and a network of tunnels and powerhouses.

• It will require the diversion of 1,165.66 hectares of forest land.

  • A hectare is a unit of area equal to 10,000 square meters.

• The estimated number of trees that will need to be felled is around 2.7 lakh (270,000).

• The Dibang Valley lies in the Eastern Himalayas, which is part of a global biodiversity hotspot.

  • A biodiversity hotspot is a biogeographic region with significant levels of biodiversity that is under threat from human activities.

• The area is rich in over 680 species of plants.

• It also harbors rare and endangered animal species.

  • These include the Mishmi takin (a type of goat-antelope native to this region), red panda, clouded leopard, and snow leopard.

  • Many bird species, some of which are endemic and threatened, are also found here. Thus, statement 3 is correct.

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