Why does external fertilization typically occur much more often in aquatic animals than in terrestrial animals? Select one: a. The gametes are hydrophobic, so they must be suspended in water to avoid clumping. b. The gametes must be produced in large numbers, which can occur only in aquatic environments. c. The gametes must be kept wet to avoid desiccation.

The correct answer is option c. "The gametes must be kept wet to avoid desiccation".

Explanation:

External fertilization is an adaption were species reproduce sexually, but there is no direct contact between the female and the male species, because the egg is fertilized outside the female's body. This adaptation occurs more often in aquatic animals because the gametes must be kept wet to avoid desiccation and allow fertilization, which occurs much more easily on aquatic environments.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."