The Structure of Reproductive Systems Is Similar Between Some Organisms

The structure of reproductive systems is similar between some organisms.What prevents fertilization of gametes from different organisms?

A) The sperm is too large or too small to fertilize the egg.
B) The large body size of one organism and the small body size of the other organism prevents internal fertilization.
C) One organism reproduces externally and the other organism requires internal fertilization.
D) Proteins on the surface of the egg and sperm are only recognized by the correct organism.
E) All answers are correct.