While reading an article for your archaeology class, you come across a section in which the author lays out a claim for the dolichocephalic Mesolithic foragers being replaced by the brachycephalic agriculturalists in Nubia. This claim that "short-headed" people came in and replaced all the "long-headed" people is likely false because
a. short-headed people would have been at an evolutionary disadvantage.
b. craniofacial changes can be attributed to long-term changes in diet rather than to wholesale population replacement.
c. long-headed people were more successful at combat because of their anatomical characteristics.
d. All of the above