Answer: <u><em> Microevolution is defined as a change in allele frequencies in a population over time. Three mechanisms can cause allele frequencies to change: natural selection, genetic drift (chance events that alter allele frequencies), and gene flow (the transfer of alleles between populations).</em></u>
Explanation:<u><em> If i'm right Mark Me brain, give 5 stars and a thank you</em></u>
The cerebrum controls the higher brain functions such as speech, writing, etc. The cerebellum deals with the involuntary stuff. The other 2 are nowhere near what you are looking for. B - Cerebrum is your answer.