The correct answer is the social exchange theory.
The social exchange theory states that social behavior is a product of interactions and exchanges between people. According to this theory, we weigh the pros and cons of a social relationship, and if there are more pros than cons we remain in the relationship, but if the cons exceed the pros, we end the social relationship. In this instance, Sophia continues to stay with her husband because she believes that the pros of doing so outweigh the cons.
