A、Physical appearance. B、Mental health. C、Body language. D、Social behavior. D

Eye contact is a meeting of the eyes between two individuals. (32) In human beings, eye contact is a form of nonverbal communication and is thought to have a large influence on social behavior. It is believed to show personal involvement and create intimate bonds. Mutual gaze narrows the physical gap between humans.
    Eye contact is a pretty important component of interacting with people. So scientists recently tested this by measuring people’s brain activity as they responded to pictures of angry people and pictures of people who look afraid. It turns out that eye contact plays an important role when people are evaluating potential threats.
    If we measured your brain activity, we’d see that the part of their brain that regulates emotions and detects potential threats is hard at work. (34) If I was staring at something and looking really frightened, your brain would work harder to figure out if whatever is scaring me may also pose a danger to you.
    Eye contact means different things in different situations. If you’re mad and looking at someone, you might be a threat. But if you’re scared and looking at me, it’s unlikely that you’re going to attack. (35) So what the study suggests is that when you’re studying emotions, you have to take eye contact into consideration. It also suggests that in uncertain situations, your brain has to do more work to process other people’s facial expressions in order to be able to evaluate the situation and respond appropriately.
32. What is eye contact thought to have a great influence on?
33. Why did scientists test eye contact by measuring brain activity?
34. What would one’s brain do when he sees the other looking frightened?
35. What does the study suggest one do when one is studying emotions?