I think that the correct answer to this question is D .
Should be called the Manubrium!
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>
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