Which of the following would you expect to occur in a captive population of guppies collected from Trinidad, if you allowed them to breed for many generations in an aquarium without any predators?

a. Female guppies will become more brightly colored.
b. Female guppies will prefer to mate with the dull-colored males.
c. The number of dull-colored male guppies will eventually equal the number of brightly colored males.
d. Male guppies that are brightly colored will have better reproductive success than dull males.