Which best describes the technique the student is using to keep his audience engaged ?

The answer is C.

Explanation:

It's not D because he's not trying to make anyone uncomfortable by just focusing on them, and shifting your focus means something different. If he were speaking clearly, slowly and as natural as possible his goal would to be understood clearly.

moon-letters were a method of writing invented by the dwarves. moon-letters were ordinary runes, but written in such a way that they could only be read when the light of the moon shone behind the writing. some moon-letters could be read by any moonlight, but it was possible to make the writing even more secret. more sophisticated moon-letters could only be read by the light of the same shape of moon, or at the same time of year, as when they were written. hope this !