UPPCS Prelims 2024 · GS Paper I: Given below are two statements, one is labelled as Assertion (A) and the other…

UPPCS Prelims 2024 · GS Paper I

Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R).

Assertion (A) : CO₂, SO₂ and NO₂ gases get dissolved in rain water and produce acid rain.

Reason (R) : Atmospheric air is polluted due to high concentration of gases like carbon dioxide, sulphur dioxide and oxides of nitrogen.

Select the correct answer from the codes given below :

Answer (a) & explanation

Option (a), both true and R explains A, is correct. The assertion is true: sulphur dioxide and nitrogen dioxide dissolve in rain water to form sulphuric and nitric acids, and carbon dioxide forms weak carbonic acid, lowering the rain's pH below about 5.6, the threshold for acid rain. The reason is true and explains it: air becomes polluted with high levels of these gases from burning coal in power plants, smelting and vehicle exhausts, which is why polluted regions get acid rain. Concept: acid rain damages forests, lakes and buildings; the yellowing of the Taj Mahal has been blamed partly on emissions from the Mathura refinery and Agra industries. The Taj Trapezium Zone was set up to protect it.

Trap

SO₂ and NO₂ form sulphuric and nitric acids in rain.

Question as printed in UPPSC's official question booklet. Source: uppsc.up.nic.in

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UPSC Prelims 2026 · GS Paper I

Which of the following statements with regard to Green Hydrogen is/are correct ?

  • 1. It is decarbonized hydrogen obtained from natural gas reforming combined with carbon capture and storage (CCS).
  • 2. It is produced using electrolysis of water with electricity generated by renewable energy.
  • 3. National Green Hydrogen Mission of India aims for abatement of nearly 50 MMT of annual greenhouse gas emissions by 2030.

Select the answer using the code given below :

Answer (b) & explanation

Statements 2 and 3 are correct (b). Statement 2 is right: green hydrogen comes from splitting water by electrolysis, using renewable power. Statement 3 is right: the National Green Hydrogen Mission (2023) targets 5 MMT of green hydrogen a year by 2030 and about 50 MMT of avoided CO₂-equivalent emissions each year. Statement 1 is wrong: hydrogen from natural gas with carbon capture is blue hydrogen. So options (a), (c) and (d) fail.

Notice the colours: grey hydrogen from gas without capture (most hydrogen today), brown from coal, and pink from nuclear power. The mission's SIGHT programme supports electrolyser making. Uses include fertilisers, refineries, steel and shipping fuel.

Trap

1 says "decarbonized", which sounds green. Gas with CCS is blue.

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Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

Which of the following statements in relation to NIRANTAR (National Institute for Research and Application of Natural Resources to Transform, Adapt and Build Resilience), a platform of institutions under the Ministry of Environment, Forest and Climate Change, is/are correct ?

  • 1. Ecosystem Survey and Analysis is a vertical under this platform, the lead institute of which is Botanical Survey of India, Kolkata.
  • 2. Research and Management of Ecosystem Service is a vertical under this platform, the lead institute of which is Central Zoo Authority, New Delhi.
  • 3. Capacity Development Support is a vertical under this platform, the lead institute of which is Indian Institute of Forest Management, Bhopal.

Select the answer using the code given below :

Answer (b) & explanation

Statements 1 and 3 are correct (b). NIRANTAR groups the Environment Ministry's institutes into verticals. Statement 1 is right: Ecosystem Survey and Analysis is led by the Botanical Survey of India, Kolkata, with bodies like the FSI and ZSI. Statement 3 is right: Capacity Development Support is led by the Indian Institute of Forest Management, Bhopal. Statement 2 is wrong: Research and Management of Ecosystem Service is led by ICFRE, Dehradun; the Central Zoo Authority is only a member. So options (a), (c) and (d) fail.

Notice the purpose: pooling institutes avoids duplicate work and links research to climate adaptation and resilience. Other Ministry bodies include the Wildlife Institute of India (Dehradun) and GBPNIHE for the Himalaya.

Trap

the Central Zoo Authority does sit in that vertical, but as a member, not the lead.

Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

Consider the following statements with reference to India’s response to climate change :

  • I. India’s Long-Term Low Emission Development Strategy (LT-LEDS) is a crucial tool for achieving net-zero emissions by 2070.
  • II. India’s 4th Biennial Update Report (BUR-4) submitted in December, 2024 recorded around 8% decrease in Greenhouse gas emissions in 2020 over 2019.
  • III. Climate-resilient development necessarily depends on quick and short-term achievement of emission reduction targets.

Which of the following relationships among the above statements is/are correct ?

  • 1. Statement I is empirically supported by statement II.
  • 2. Statement III contradicts the approach implicit in statement I.
  • 3. Statement I and statement III together establish the premise of long-term sustainability.

Select the answer using the code given below :

Answer (b) & explanation

Relationships 1 and 2 are correct (b). Relationship 1 is right: the LT-LEDS (2022) lays out India's path to net zero by 2070, and BUR-4 reported a fall of about 7.9% in 2020 emissions over 2019, real data in line with that path. Relationship 2 is right: Statement III wants quick, short-term cuts, while the LT-LEDS is a long, gradual plan, so III contradicts I. Relationship 3 is wrong: two contradicting statements cannot together set a premise. So options (a), (c) and (d) fail.

Notice the cause of the 2020 fall: the COVID-19 lockdowns, not a lasting trend. India's updated NDC (2022) targets cutting emissions intensity of GDP by 45% from 2005 levels by 2030. Biennial Transparency Reports now replace BURs.

Trap

"together establish" sounds positive, but two statements that clash cannot form one premise.

Answer as per the official UPSC answer key.

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UPSC Prelims 2026 · GS Paper I

With respect to the Western Hoolock Gibbons, which of the following statements is/are correct ?

  • 1. A Sanctuary in North-east India is home to this ape species listed as Endangered in the International Union for Conservation of Nature (IUCN) Red List.
  • 2. They have specialized brachiation and can easily swing between trees.
  • 3. They possess a strong and heavy build like gorillas, yet are remarkably agile tree climbers.

Select the answer using the code given below :

Answer (b) & explanation

Statements 1 and 2 are correct (b). Statement 1 is right: India's only ape, the western hoolock gibbon, is Endangered on the IUCN Red List and gives its name to the Hollongapar Gibbon Sanctuary in Assam. Statement 2 is right: gibbons move by brachiation, swinging arm over arm through the canopy. Statement 3 is wrong: they are "lesser apes", slim and light, about 6–9 kg, nothing like a heavy gorilla. So options (a), (c) and (d) fail.

Notice their habits: they live in pairs with their young and sing loud duets at dawn. They are found south of the Brahmaputra in the North-East. Rail lines cutting through Hollongapar have raised concern, and canopy bridges were proposed to help them cross.

Answer as per the official UPSC answer key.

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