Step 1: Understanding the Concept:
Sociologist Charles Horton Cooley introduced the distinction between primary and secondary groups.
Primary groups are small social groups whose members share close, personal, enduring relationships. These relationships are marked by mutual concern, and they are ends in themselves.
Secondary groups are large, impersonal groups whose members pursue a specific goal or activity. Relationships are often temporary and instrumental.
Step 2: Detailed Explanation:
(A) Family: The family is the archetypal primary group. It is characterized by intimate, face-to-face, long-lasting relationships based on emotional connection.
(B) Political party: This is a secondary group. Members are united by a common ideology or goal, and interactions are typically formal and impersonal.
(C) Class: A school class is a secondary group. Students and the teacher come together for the specific, instrumental purpose of education.
Step 3: Final Answer:
The family is the best example of a primary group among the choices provided.