Anthropologists Have Observed That Chimpanzees Can Use Stone Tools to Crack

Anthropologists have observed that chimpanzees can use stone tools to crack nuts, and that they teach this useful skill to their offspring. This is significant because chimpanzees:

A) are actively evolving.
B) are capable of social learning.
C) are not very intelligent primates.
D) may evolve to pose a threat to human life.