Chloe debated for a long time about whether to take a psychology or a sociology course, both of which looked interesting. She finally chose the psychology course. Now, because she is experiencing , she raves about the psychology course to her friends.

postdecision dissonance        

Explanation:

Post-decision dissonance: In psychology, the term "post-decision dissonance" is referred to as one of the categories of cognitive dissonance. An individual who experiences post-decision dissonance encounters distress that generally arises once he or she makes a specific decision about something. According to psychologists, whenever an individual makes a decision related to something which is considered as desirable for the person causes dissonance.

In the question above, Chloe is experiencing "post-decision dissonance".

answer8.3 months;