Explanation
- A
1 and 2 only
1 and 2 only. Soil carbon also holds.
- B
2 and 3 only
2 and 3 only. Wheat after rice without burning also holds.
- C
3 only
3 only. Under-counts.
- D
1, 2 and 3
All three. Wheat into rice residue without burning; wet direct-seeded rice without a nursery; carbon left in the soil.
Summary. Official key is (d) 1, 2 and 3. Zero tillage lets wheat go in without burning paddy stubble, allows direct-seeded rice, and keeps carbon in the soil.
Same topic · past papers
UPSC has asked this before
These previous-year questions sit on the same topic. Open one to practise the earlier ask.