A population of 15 birds inhabits a small island. Ten of the birds are dark brown, and five of them are light brown. By chance, two of the dark brown birds and three of the light brown birds die before producing any offspring. All of the birds in the next generation are dark brown. This change in phenotypic frequency can be attributed to __________.

a. natural selection
b. gene flow
c. sexual selection
d. genetic drift


Answer: d. genetic drift

Biology & Microbiology

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