Correct answer: (c) 2 and 3 only
Explanation
- A
1 and 3 only
(a) 1 and 3 only. Nitrate leaching (3) is real, but statement 1 is the wrong way round: surplus mineral nitrogen typically suppresses, not proliferates, symbiotic nitrogen-fixers. Including 1 knocks this option out.
- B
2 only
(b) 2 only. Acidification from ammonium/urea fertilisers is correct, but leaching of nitrate is also a standard impact. 2 only is incomplete.
- C
2 and 3 only
(c) 2 and 3 only. Excess nitrogenous fertiliser can acidify soil and send nitrate into groundwater. It does not cause a bloom of nitrogen-fixing microbes. Statements 2 and 3 are the valid pair and the official key.
- D
1, 2 and 3
(d) 1, 2 and 3. Statement 1 is incorrect, so the full set cannot be the key.
Summary. Official key is (c) 2 and 3 only. Overuse of nitrogenous fertilisers can raise soil acidity and leach nitrate to groundwater. Nitrogen-fixers are not encouraged by a nitrate glut; they are often outcompeted. Statement 1 is therefore false. The keyed pair is acidification plus leaching.
PYQ trend
When UPSC asked this
Related PYQs from other years, newest first. Open a question to read it.
-
2018 · Q2 · General Studies · 2 marks
Which of the following leaf modifications occur(s) in the desert areas to inhibit water loss? 1. Hard and waxy leaves 2. Tiny leaves 3. Thorns instead of leaves Select the correct answer using the code given below: -
2017 · Q14 · General Studies · 2 marks
In the context of solving pollution problems, what is/are the advantage/advantages of bioremediation technique? 1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature. 2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms. 3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation. Select the correct answer using the code given below: -
2017 · Q21 · General Studies · 2 marks
Due to some reasons, if there is a huge fall in the population of species of butterflies, what could be its likely consequence/consequences? 1. Pollination of some plants could be adversely affected. 2. There could be a drastic increase in the fungal infections of some cultivated plants. 3. It could lead to a fall in the population of some species of wasps, spiders and birds. Select the correct answer using the code given below: -
2017 · Q60 · General Studies · 2 marks
With reference to the role of UN-Habitat in the United Nations Programme working towards a better urban future, which of the following statements is/are correct? 1. UN-Habitat has been mandated by the United Nations General Assembly to promote socially and environmentally sustainable towns and cities to provide adequate shelter for all. 2. Its partners are either governments or local urban authorities only. 3. UN-Habitat contributed to the overall objective of the United Nations system to reduce poverty and to promote access to safe drinking water and basic sanitation. Select the correct answer using the code given below: -
2017 · Q71 · General Studies · 2 marks
Which of the following statements can help in water conservation in agriculture? 1. Reduced or zero tillage of the land 2. Applying gypsum before irrigating the field 3. Allowing crop residue to remain in the field Select the correct answer using the code given below: -
2015 · Q12 · General Studies · 2 marks
With reference to the International Union for Conservation of Nature and Natural Resource (IUCN) and the Convention of International Trade in Endangered Species of Wild Fauna and Flora (CITES), which of the following statements is/are correct? 1. IUCN is an organ of the United Nations and CITES is an international agreement between governments. 2. IUCN runs thousands of field projects around the world to better manage natural environments. 3. CITES is legally binding on the States that have joined it, but this Convention does not take the place of national laws. Select the correct answer using the codes given below -
2015 · Q19 · General Studies · 2 marks
With reference to 'dugong', a mammal found in India, which of the following statements is/are correct? 1. It is a herbivorous marine animal. 2. It is found along the entire coast of India. 3. It is given legal protection under Schedule I of the Wildlife (Protection) Act, 1972. Select the correct answer using the codes given below -
2015 · Q49 · General Studies · 2 marks
Which of the following statements regarding 'Green Climate Fund' is/are correct? 1. It is intended to assist the developing countries in adaptation and mitigation practices to counter climate change. 2. It is founded under the aegis of UNEP, OECD, Asian Development Bank and World Bank. Select the correct answer using the codes given below