To exasperate someone is to:

To exasperate someone means to make them very annoyed or angry. The term originates from the Latin word "exasperare," which means to irritate or make rough. When someone is exasperated, they typically feel overwhelmed by frustration, often due to repeated annoyances or challenges that test their patience. This aligns perfectly with the correct answer, as it captures the essence of the emotional response associated with exasperation.

The other choices suggest positive actions that involve assisting or supporting someone, which are completely contrary to the feeling of exasperation. Helping someone understand or encouraging their efforts would likely lead to a sense of satisfaction or gratitude, rather than frustration. Hence, the correct choice reflects the negative emotional impact one might have on another individual.