Question

which of these is a type of genetic drift?
bottleneck effect
natural selection

Explanation:

Genetic drift refers to random changes in allele frequencies in a population. The bottleneck effect is a type of genetic drift where a population size is drastically reduced (like through a natural disaster), leading to a change in allele frequencies. Natural selection is a different evolutionary mechanism where organisms with favorable traits are more likely to survive and reproduce.

Answer:

Bottleneck effect