Option 1 suggests that only some species of turtles and marine mammals are herbivores. This is partially true, but leaves out other herbivorous species such as some types of fish.

Option 2 suggests that some species of fish and marine mammals are herbivores and some species of snakes are viviparous (give live birth instead of laying eggs). This does not include herbivorous turtles.

Option 3 only considers herbivorous fish and viviparous snakes. It does not include herbivorous turtles or marine mammals.

Option 4 is the correct answer. It correctly identifies that some species of all four types of animals in question - turtles, fish, marine mammals, and snakes - can be herbivorous or viviparous. Some species of turtles, fish, and marine mammals do feed on plant life, and there are species of snakes that are viviparous. Hence, all four statements are correct.