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?

The correct option is 1, 2, 3 and 4.

Let us analyze each statement step-by-step to understand why all of them are correct:

Statement 1: Some species of turtles are herbivores.
This statement is correct. While many turtle species are omnivorous or carnivorous, adult green sea turtles (Chelonia mydas) are predominantly herbivorous, feeding mainly on sea grasses and algae.

Statement 2: Some species of fish are herbivores.
This statement is correct. Several fish species feed exclusively on plant matter, algae, and seaweeds. Examples include parrotfish, surgeonfish, and certain species of tilapia and catfish.

Statement 3: Some species of marine mammals are herbivores.
This statement is correct. Sirenians, which include manatees and dugongs, are fully aquatic, herbivorous marine mammals that graze on aquatic vegetation and seagrasses.

Statement 4: Some species of snakes are viviparous.
This statement is correct. Although most snake species lay eggs (oviparous), some species give birth to live young (viviparous or ovoviviparous), especially those living in colder climates. Examples include garter snakes, green anacondas, and boa constrictors.

Since all four statements are scientifically accurate, the correct combination is 1, 2, 3 and 4.