What is the most important reason for speakers to use visual aids?
a. to introduce material not covered in the speech
b. to use as a crutch during a long speech
c. to delivery additional statistics
d. to keep the audience engaged

It could be letter c. delivery of additional statistics.  This is to provide more support for the topic of the speech by presenting relevant data connected with your speech.  It can also be letter d. keep audience engage because visual aids keep the audience focus on the speech and helps them understand it better.

specific audience will understand the main ideas. for example, if you were writing an instruction manual for rocket scientists, it would likely look very different from one you would write for young children. your language, tone, and writing style would change significantly.

the answers are;

d. it reveals hamlet’s hesitation to act.

a.it reveals hamletâs anger with himself.