Final answer:
Genetic drift is a random change in allele frequencies that occurs in a small population due to random fluctuations in the number of offspring produced by a small number of parents.
Step-by-step explanation:
Genetic drift is a random change in allele frequencies that occurs in a small population. This phenomenon is caused by random fluctuations in the number of offspring produced by a small number of parents. It can lead to significant changes in a population's genetic structure over time.