Answer:
b. his eye contact.
Step-by-step explanation:
Eye contact defines that it occurs when two people look at each other at the same time. It is a part of non-verbal communication when two people look at each other and thus its impact on social behavior.
Now, According to the given situation, Trevor gets a haircut and he dressed well for the interview. He is entering into the room of interview, wished and shake his hand to the interviewer after looking into his hand. Here, Trevor needs to improve his eye contact with their skills and abilities at the time of the interview.