The classic Robber's Cave study showed that prejudice can be reduced by ________.

A) mere exposure
B) relearning social norms
C) cooperating to meet a mutually beneficial goal
D) rethinking one's stereotypes

The Robber's Cave study demonstrated that prejudice could be reduced by cooperating to achieve a mutually beneficial goal. The study involved two groups of boys who initially exhibited prejudice towards each other but eventually formed friendships after being brought together to achieve shared goals. This suggests that intergroup cooperation can promote positive attitudes and reduce prejudice. Options A, B, and D are all possible ways to reduce prejudice, but the Robber's Cave study specifically demonstrated the effectiveness of intergroup cooperation.