According to social exchange theory, an individual’s primary motive in establishing and maintaining relationships is

a. maximizing rewards and minimizing costs.
b. achieving an equitable balance of inputs and outputs.
c. maintaining reciprocal levels of self-disclosure.
d. the reproductive fitness of a potential partner.

a.maximizing rewards and minimizing costs.      

Explanation:

Social exchange theory was proposed by a famous sociologist named George Homans and is described as the tendency of individuals to weigh the risk of social relationship and potential benefits. In other words, the theory says that an individual's social behavior is often considered as the consequence of an 'exchange process' and the purpose associated with exchange is to minimize costs and maximize benefits.

The correct answer for the question is a.