Conservation Biologists Are Often Concerned That When the Population Size

Conservation biologists are often concerned that when the population size of an endangered species becomes too small,it is at risk of extinction for which reason?

A) They are at risk of developing prezygotic barriers to reproduction.
B) They can no longer evolve.
C) They may be more susceptible to changes in the environment or disease.
D) They are at risk of sympatric isolation.
E) Their rate of breeding will decline.