Which of these is a factor that can reduce a group's attractiveness and cohesiveness?

A) Prestige and status
B) Competition for membership by other groups
C) Relatively small size
D) A common threat in the environment
E) Similarity of members

Competition for membership by other groups can reduce a group's attractiveness because it creates a sense of conflict and divisiveness within the group. Members may feel pressure to choose between multiple groups or may become disillusioned with their current group if they perceive another as more appealing. This can ultimately reduce cohesiveness and commitment to the group.