________ is a primary agent/agency of socialisation for very young children.

Correct option is D

(d) Immediate family
For very young children, the immediate family serves as the primary agent of socialization. In the early years, family members, especially parents and siblings, play a critical role in shaping a child's social behaviors, values, norms, and attitudes. This early socialization within the family forms the foundation for later interactions and socialization in broader society.