Refer to the Scenario Below, and Then Answer the Following

Multiple Choice

Refer to the scenario below, and then answer the following question(s) .
Two European men and two Polynesian women settled on a previously uninhabited tropical island. All four of the settlers have brown eyes, a dominant trait, but one of the Europeans is heterozygous and carries the recessive gene for blue eyes.
-No new settlers arrive,and nobody leaves the island.After a few generations,the percentage of blue-eyed individuals increases from the original zero to 25 percent.This is probably due to which of the following factors?

A) genetic drift
B) mutation
C) gene flow