A population of 1,000 birds exists on a small Pacific island. Some of the birds are yellow, a characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. By chance, only ten birds remain, and those birds all have yellow feathers.

Below are several statements about this hypothetical situation.

a. Assuming that no new birds come to the island and no mutations occur, future generations of this population will contain both green and yellow birds.
b. Assuming that no new birds come to the island and no mutations occur, future generations of this population will contain only yellow birds.
c. This situation represents diversifying selection.
d. This situation represents directional selection.