Identify the following statements about the evolutionary development of group membership as either true or false.

a. Humans are unique in our pervasive tendency to form groups.
b. Humans have the largest group size of all primates and also the largest prefrontal cortex.
c. Humans developed more cognitive resources to deal with the many challenges that come from living in large groups.
d. We are motivated to form groups because living in social groups helped our ancestors survive.