<span>Ethos is an appeal to ethics, and it is a means of convincing someone of the character or credibility of the persuader.
</span><span>examples.yourdictionary.com/examples-of-ethos-logos-and-pathos.html</span>
using process of elimination you can eliminate condescending and pessimistic, and the passage doesn't really seem humorous either so your left with enthusiastic. The author seems to be happy and excited to share knowledge about how literature can make people feel, thus the best answer choice is probably enthusiastic
