UPSC Prelims 2021— Question 41

Permaculture emphasizes ecological design, diversity, recycling of resources, soil protection and practices such as mulching. It generally discourages monoculture and seeks systems that can function with ecological inputs. Conventional chemical farming can involve monoculture and may contribute to salinity under unsuitable irrigation and fertilizer management. The accepted combination is statements 1, 2 and 4. The final answer-key position for Set C identifies option B as the correct option. Option A — 1 and 3 — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. Option B — 1, 2 and 4 — is correct because it is the alternative that matches the constitutional, historical, geographical, scientific or economic principle established above. Option C — 4 only — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. Option D — 2 and 3 — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. For PYQ interpretation, the distinction between the correct alternative and merely related facts is important. UPSC often places plausible distractors beside the precise statement that matches the underlying rule, chronology, definition or empirical relationship. The answer should therefore be read against the exact wording of the question rather than against a broadly related fact.