Adult male humans generally have deeper voices than do adult female humans, which is the direct result of higher levels of testosterone causing growth of the larynx. If one excludes the involvement of gender in the situation, then the pattern that is apparent in the fossil record is most similar to one that should be expected from

A. pansexual selectionB. directional selectionC. disruptive selectionD. stabilizing selection

disruptive selection

Explanation:

Disruptive selection is the natural selection that favors two extreme phenotypes but does not favor the intermediate phenotype. Here, the survival and reproductive success of two extreme phenotypes are higher than that of the intermediate phenotype due to their higher fitness value in the prevailing conditions. The presence of deeper voices in males and less deep voices in females due to high and low levels of testosterone respectively represents the disruptive selection as the phenotype present at two extreme ends are favored.

C. Disrupted selection