Genetic equilibrium and gene frequencies would be maintained by all but which one of the following?

Question

A. large population interbreeding freely,

B. random mating,

C. development of isolation mechanisms,

D. differential mating and survival,

E. all the above

Answer 1

Hardy-Weinberg equilibrium will hold in large populations mating at random, but deviations from it will be observed when there is nonrandom mating and selection.

So, it will hold under conditions A. and B. but not C. or D., provided that the development of reproductive isolation is affecting within gene pool dynamics. If so, that will amount to differential mating, making it equivalent to D. If not, then go with D. as your answer, because nonrandom mating and selection will definitely lead to deviations from Hardy-Weinberg expectations.