Correct Response: B. The Hardy-Weinberg equilibrium model states that the frequencies of alleles in the gene pool will remain unchanged in the absence of evolutionary factors. Stability in the gene pool depends on a number of factors, including the condition that all members of the population breed and that mating is random. If sexual selection occurs, the frequency of alleles in the gene pool changes. Variable environmental conditions (A) and a high level of phenotypic diversity (C) are not assumptions made in the Hardy-Weinberg equilibrium model. A large population size (D) is a requirement of the Hardy-Weinberg model, so this condition would support, rather than violate, the model.
