Answer:
The correct answer is : Cognitive dissonance theory.
Step-by-step explanation:
The cognitive dissonance theory states that individuals have a tendency to allign their thoughts, opinions and attitudes to their behavior and decisions.
A dissonance occurs when said attitudes and opinions don't match with their behaviors which causes the individual to experience stress. The individual then has two options: 1- Either he/she changes his/her behavior or 2- He/She modifies his/her attitudes toward the behavior.
In this case Sonya's attitude toward sororities was negative because she thought sororities were filled with snobs and that she would never consider joining one. Then she went to a social function of a sorority. Here, the dissonance appeared and she decided to modify her attitude toward sororities which illustrates the Cognitive dissonance theory.