Passage 4 Questions 16 to 20 are based on the following passage. Regular interaction or familiarity seems to increase liking; often, the people we interact with the most are simply those who are closest to us. A classic study by Festinger found that residents of an apartment complex tended to interact with, and like those who happened to live on the same floor more than those who lived on other floors or in other buildings. The researcher did not yze this phenomenon in terms of the development of in-group versus out-group perceptions and biases, but such an ysis might prove interesting. Likewise, when classroom seating is alphabetical (依字母顺序的), students are more likely to be friends with people who share the same initial. There are two major explanations for the relation between proximity (接近) and liking. The first is availability. If most people are nice and easy enough to approach, it follows that proximity will determine who you get to know and, therefore, like. The second explanation is based on the mere exposure effect, that is, familiarity increases liking for a person or object that is not necessarily likeable. The mere exposure effect has been demonstrated in the laboratory with some meaningless syllables, which people find more pleasing after they have repeated them several times. It seems reasonable to conclude that repeated exposure to people in proximity to us leads us to like them more. The experiment on the meaningless syllables is intended to demonstrate that ______.