A Series of Studies on the Generation and Reduction of Intergroup

A series of studies on the generation and reduction of intergroup hostility was conducted on boys at summer camp by Sherif and his coworkers. Which of the following was found to be false for the generation of hostility?

A) Hostility was difficult to generate because the boys hardly knew each other at first.
B) Separating the boys into group residence cabins increased the hostility between the residence groups.
C) Giving the groups names, like the Bull Dogs and Red Devils, increased hostility between the groups.
D) Engaging the groups in competitions greatly increased hostility.