If the Frequency of the Recessive Allele That Causes Phenylketonuria

Multiple Choice

If the frequency of the recessive allele that causes phenylketonuria (PKU) when homozygote is about 0.01 in European and American populations,what is the estimated heterozygote frequency in these populations? (Assume that people mate randomly with respect to PKU,and that the mutant allele does not have any effects on fitness.)

A) about 0.0001
B) about 0.01
C) about 0.0198
D) about 0.99
E) It is impossible to make an estimate.