What Accounts for the Fact That Polydactylism Is Prevalent and Tay-Sachs

question 21

Multiple Choice

What accounts for the fact that polydactylism is prevalent and Tay-Sachs disease is virtually absent in one human population in the United States, while Tay-Sachs disease is prevalent and polydactylism is virtually absent in another?

• A)Natural selection has promoted these differences since humans live in many different environments.
• B)Mutation rates differ among different loci.
• C)There is little gene flow between the two populations.
• D)The populations are small, and therefore genetic drift is a major factor in the determination of allele frequencies.
• E)The alleles are fixed in these populations.