The number of trout in a lake drops when the lake is polluted. the trout population later increases, but the allele frequency is different than it was before the pollution. what type of situation is this?

a. founder
b. mass extinction
c. genetic drift
d. bottleneck

"Bottleneck" is the type of variation among the choices that are given in the question is being described by the situation. The correct option among all the options that are given in the question is the fourth option or option "D". I hope that this is the answer that has immensely helped you.