The Recruitment of Coral Reef Fishes Seems to Be the Result

The recruitment of coral reef fishes seems to be the result of one of these phenomena:

A) Species tend to avoid competition.
B) Each species has its own ecological niche but it is modified to avoid direct competition.
C) Corals over compete other organisms as long as they keep their zooxanthellae.
D) The outcome of competition is based mostly on chance.
E) Species actually chose when to compete and when to move elsewhere.