The correct answer is B. Characterized by intimate, face-to-face association and cooperation.
Explanation:
Primary groups include small groups composed of individuals who interact constantly, cooperate to achieve common goals, have a sense of belonging and share common interests. An example of primary groups is families because they interact daily, cooperate to take of each other and share common interests and backgrounds. Moreover, primary groups differ from secondary groups due to their level of interaction and cooperation because in primary groups this is intimate and constant. This implies, a primary group is "characterized by intimate, face-to-face association and cooperation".