Question

focus on how people use messages to influence each other in various contexts and cultures, using a variety of media.
A. Public speakers
B. Radio personalities
C. Motivational speakers
D. Communication researchers

Answer 1

This is not a sentence or a question:
<i>focus on how people use messages to influence each other in various contexts and cultures, using a variety of media.</i>

It reads as if it's a definition of some term in your text. Go back into your text to find it.

Answer 2

Yes, Writeacher is correct. What are you supposed to do with this non-sentence, and how can we help you?

Answer 3

Your supposed to find which term fits that definition

Answer 4

It's d btw. Communication researchers

Answer 5

D. Communication researchers