题目内容：

A team of US psychologists(心理学家) have found that talking to another person for ten minutes a day helps with memory.

“Socializing(交际) is just as effective as more traditional kinds of mental exercise in boosting memory and intellectual(智力的) performance,” Oscar Ybarra, a psychologist at the University of Michigan Institute for Social Research, said in a statement.

In one investigation, they analyzed data on 3610 people, aged 24 to 96.

They found that the higher their level of social interaction(交流), the better their cognitive(认知的) functioning. Social interaction includes getting together or having phone chats with relatives, friends and neighbors.

In another experiment, the researchers conducted laboratory tests on 76 college students, aged 18 to 21, to evaluate(评估) how social interactions and intellectual exercises affected the results of memory and mental performance tests.

The students were divided into three groups: the social interaction group had a discussion of a social issue for 10 minutes before taking the tests; the intellectual activities group completed three tasks (including a reading comprehension exercise and a crossword puzzle) before the tests; and a control group(对照组) watched a 10-minute clip(电影片段) of the Seinfeld television show.

“We found that short-term social interaction lasting for just 10 minutes improved participants’ (参与者) intellectual performance as much as engaging in (从事) so-called ‘intellectual’ activities for the same amount of time,” Ybarra said.

The study was expected to be published in the February issue of the journal Personality and Social Psychology Bulletin.

1.What does the underlined word “boosting” in the second paragraph probably mean?

A. Improving.   B. Reducing.

C. Preventing.   D. Training.

2.Which is not included in social interaction?

A. Having a talk with a neighbor.

B. Attending a birthday party.

C. Watching TV at home alone.

D. Calling your classmates.

3.What’s the purpose of the experiment on 76 college students?

A. To judge the effect of social interaction on memory and intelligence.

B. To find out what is real social interaction.

C. To learn how much time is needed for social interaction.

D. To show the function of people's cognition.

4.What’s the main idea of the passage?

A. Intellectual exercises make your memory better.

B. Different people have different ways of communication.

C. Communicating with others keeps you healthy.

D. Social interaction makes you smart.