Although All of the Following May Have Been Critical to the Development

Multiple Choice

Although all of the following may have been critical to the development of an expanding brain, which do scientists believe would have contributed most directly to brain growth?​

A) ​the migration into colder and less known areas placing a premium on learning
B) ​a genetic mutation resulting in a smaller jawbone and smaller facial muscles
C) ​the detoxification of foods, allowing humans to live to significantly older ages
D) ​the ability to conquer predators, allowing humans higher meat consumption levels