Researchers Studying Guppies in Trinidad Found That Guppies in Streams

Multiple Choice

Researchers studying guppies in Trinidad found that guppies in streams with high predation reproduced earlier and more frequently.Which of the following is most important in driving the guppies to change their life history in face of predation?

A) The guppies are an equilibrium species.
B) The guppies are an opportunistic species.
C) Density-independent factors affect the guppy populations.
D) Density-dependent factors affect the guppy populations.
E) Sexual selection affects the guppy populations.