Answer: a) agents of socialization
Step-by-step explanation:
Agents of socialization is defined as the representative that makes an individual familiar with the social environment. People like friends, family, guardian, teacher , media etc are the factors that act as the agent to make an individual familiar with the society.
They make the person learn about the qualities, requirements, behavior, expression,reaction and other such characteristics to deal and participate in social world.
Other options are incorrect because roles sets are the collection of social roles. Interaction forums is the organization for that regards with influence, interacts and motivates.Sources of social reference is in which infants understand the world with the help of adults.
Thus, the correct option is option(a).