Final answer:
The family (option c) is the earliest and most pivotal agent of socialization, significantly influencing an individual's societal and political perspectives from early childhood.
Step-by-step explanation:
The first and most important instrument of socialization is the family. From birth, family members such as parents, siblings, and extended relatives begin the process of socialization by teaching children about the world around them. This includes how to interact with others, understanding societal norms, and forming the initial views and attitudes that will shape their adult lives. Consequently, the family has a profound impact on both general socialization and political socialization, influencing one's views on a wide range of topics including religion, work, and education.
It’s important to note that this influence is not unidirectional. For instance, the activism of individuals like Greta Thunberg shows how younger generations can impact the opinions and behaviors of their family. However, the consensus in social studies is that the family serves as the earliest agent of socialization, setting the foundation for an individual's integration into society.