Which of these would, if it had acted upon a gene, prevent this gene from acting as a reliable molecular clock?
A)neutral mutations
B)genetic drift
C)mutations within introns
D)natural selection
E)most substitution mutations involving an exonic codon's 3rd position

Question

Quizplus · Accepted Answer

Natural selection can act to selectively remove or favor mutations in a gene, which would prevent it from reliably ticking like a clock. If a gene is under strong selective pressure, certain mutations may be preferred or disfavored, leading to a different rate of evolution than expected based on the assumption of a neutral molecular clock.

Which of These Would, If It Had Acted Upon a Gene