阅读理解:阅读下列短文, 从所给的四个选项中, 选出最佳答案。 

    Animals seem to have the sense to eat when they are hungry and   they do not eat more than their bodies need. It has been demonstrated   (证实) that rats will, when given a choice over a period of time,   prefer water with vitamins (维生素) to water without vitamins, even   though there is no difference in taste or smell between the two water   bottles. When a fragrant flavor (香味) was added to the   vitamin—enriched liquid, the rats did seem to develop a taste for it   and kept drinking it, even after the vitamins were switched (转) to   the clear water. In time, however, they broke the habit and went back   to where the necessary vitamins were.

  

      In an experiment, babies of 6 to 12 months old were placed in a   cafeteria (自助食堂) with a wide selection of baby food before them.   They were given whatever food they pointed to or appeared interested   in. We are told that at first they showed some unusual eating   patterns, but over a period of time they managed to select a well   balanced diet (饮食).

  

       So, in selecting food, rats and babies do seem to know and act on   what's best for them. Clearly, there is a kind of "body wisdom" which   humans soon lose. Most of us do not eat as wisely as we could. Many   of our food preferences are culturally determined and influenced (影   响) by long-established habits. Some people eat fox, dog and   blackbirds, while we eat cows and pigs. So what people eat and how   much they eat seems to be greatly influenced by what is going on   around them.  

  

(1)In the experiment on rats, a fragrant flavor was added to the   rat's drinking water to ________.

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A. encourage rats to drink it     

B. find out what kind of flavor rats prefer     

C. test whether rats know which drink is with fragrant flavor     

D. demonstrate that vitamins are tasteless     

(2)The expression "the habit" in the first paragraph refers to   drinking water which __________.          

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A. has no smell   B. is tasteless

C. has vitamins   D. is flavored     

(3)As far as their eating habits are concerned, babies and rats   are similar (相似) because ___________.      

  

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A. both have the wisdom to choose a balanced diet     

B. both prefer flavored food and drink     

C. both have the same eating patterns     

D. both develop a taste for the same kinds of flavors     

(4)In the experiment mentioned in the second paragraph, babies   were _________.

A. given many choices of drinks     

B. provided with various kinds of baby food     

C. placed and fed in a cafeteria     

D. trained to select a balanced diet     

(5)According to the passage, adults' (成年人) eating habits differ   from those of babies because ____________.    

  

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A. adults know better than babies what kinds of food are good for their health     

B. adults usually cannot resist the temptation of various delicious foods     

C. adults' eating habits are closely related to the social and cultural customs     

D. adults have more choices of food than babies in eating patterns