Why is it more common for birds to have nests with a few eggs rather than just one or a lot?

Female birds have one working ovary, unlike mammals, which have two. Ovaries are the organs where eggs are produced. A bird's ovary looks like a tiny bunch of different-sized grapes.

b is the best answer for this question.

explanation:

on disadvantage of hydroelectric power is the cost. another disadvantage of using hydroelectric power is finding a water source powerful enough to harvest hydroelectric power.