Why Do Even Minimal Differences Between Individuals (E

Why do even minimal differences between individuals (e.g." differences in the ability to correctly estimate the number of dots on a computer screen) result in self-categorization and the formation of social identities?

A) Making in-group/out-group distinctions allows for the survival of the species.
B) People have a need to see themselves in a favorable manner in relation to others.
C) Self-categorization enables people to focus on those aspects of the environment meaningful to the interaction at hand.
D) Self-categorization enhances exchange outcomes" since groups are better able than individuals to secure valued rewards.
E) both b and c