Jarl makes several minor mistakes during his conversational French class. Instead of thinking, "everyone makes mistakes sometimes," he thinks, "I am so stupid." What kind of cognitive distortion is this?

Over-generalization

Explanation:

Over-generalization is a common issue among the people who are suffering from some mental disorder depression, an anxiety disorder. It is the process of thinking in which you apply one experience and generalizes it on other all experience including those happened in the future.

For example, you have given a speech that was not good but you generalized it in future also that next time i did the same things that lead to over-generalization. It can worsen the thought of a person which leads to anxiety, depression, aggression, frustration, etc and everyone starts to dislikes you. There is another condition in which the person limited his potential.