A. The two character's communication indicate how they both feel, and think of each other. It too, reflects their personalities when both characters talk to each other. For example, say 'hi' to Bob. If Bob speaks friendly with Fred, we know that Bob is a nice guy!!
B. The setting doesn't reflect how the characters act since it doesn't reveal anything about the character.
C. The background information MAY be helpful to determine their personalities, although it doesn't reflect their current personalities, nor does it reflect how both characters act toward one another. However, without A as an option choice, this would have been the best answer choice.
D. Okay, transition words, don't reflect ANYTHING about the character. Sorry transition words :(
A their communication