Consider the following statements : 1. Some species of turtles are herbivores. 2. Some species of fish are herbivores. 3. Some species of marine mammals are herbivores. 4. Some species of snakes are viviparous. Which of the statements given above are correct?

(a) 1 and 3 only
(b) 2, 3 and 4 only
(c) 2 and 4 only
(d) 1, 2, 3 and 4 ✓ UPSC's answer

Why the answer is (d)

• Statement 1 is correct: green sea turtles are herbivores, grazing on seagrass and algae.

• Statement 2 is correct: many fish — parrotfish, surgeonfish, grass carp — feed on algae or plants.

• Statement 3 is correct: manatees and dugongs (sea cows) are herbivorous marine mammals; the dugong is found in India's Gulf of Mannar and Palk Bay.

• Statement 4 is correct: several snakes, including boas, vipers, sea snakes and garter snakes, give birth to live young (viviparous/ovoviviparous).

• Hence 1, 2, 3 and 4, option (d).

Why the other options are wrong

(a) 1 and 3 only: Herbivorous fish and viviparous snakes also exist.
(b) 2, 3 and 4 only: Herbivorous turtles (green turtle) also exist.
(c) 2 and 4 only: Herbivorous turtles and marine mammals also exist.

Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2019, held on 2 June 2019. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.