For days, Dianne had been trying to think of a way to approach her parents about her desire to transfer to a new college. While watching a TV commercial about vacation areas, Dianne suddenly looked at her problem from a new perspective and thought of a solution. Dianne's behavior BEST illustrates:

the occurrence of insight

Explanation:

Dianne wants to go to a college to which her parents oppose. She is thinking of ways to persuade them. In thinking about the ways she stumbles upon an advertisement which says her college is a place which is vacation area.

She did not know this before. She thought that telling her parents that her college is in an area that is a vacation area would persuade them as they could go on vacation where their daughter was staying.

Hence, the question is referring to the occurrence of insight.