Answer: Out-group members create cohesiveness in the group.
Explanation: Out-group members are the people who do not belong to any particular gathering or group. These people are not identified by the people of any certain group.
These groups are not given respect equal to the in-group members, might produce non-positive impact on collaborative group and they oppose the building of community.
The only incorrect option is that these group have cohesiveness because they don't unite the members of the group or gathering.