Answer:
It means that the marginal cost of going to the movies is less than the marginal benefit of going to the movies.
Explanation:
If the student chooses to go to the movies, it means that he thinks he has less to lose when he foregoes studying for a test. Even though logically it may appear that the latter would be a better option, according to him, the 2 or so hours at the movies would provide an extra value like if he went with a family member who he cares about. That probably beats the cost of staying up late to revise for the test.
