Altruistic Behaviors Differ from Prosocial Behaviors in That

Altruistic behaviors differ from prosocial behaviors in that

A) prosocial behaviors involve other people and are more social.
B) altruistic behaviors are voluntary and prosocial behaviors are not.
C) altruistic behaviors benefit other people while prosocial behaviors do not.
D) altruistic behaviors involve the willingness to help another without any expectation of reciprocity.