单选题
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 that rats will, when given a choice over a period of time, prefer water with vitamins to water without vitamins even though there is no difference in taste or smell between the two water bottles. When a fragrant flavor was added to the vitamin-enriched fluid, the rats did seem to develop a taste for it and kept drinking it, even after the vitamins were switched to the clear water. In time, however, they broke the habit and went back to where the necessary vitamins were. In a classic experiment, babies of 6 to 12 months old were placed in a cafeteria feeding arrangement, 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 that over a period of time they managed to select well-balanced diet. So, in selecting food, rats and babies do seem to know and act on what's best for them. Apparently, 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 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.
单选题
In the experiment on rats, a fragrant flavor was added to the rat's drinking water to ______. A. encourage rats to drink vitamin-enriched water B. find out rats preference in flavor C. test whether rats know which drink is good for them D. demonstrate that vitamins are tasteless
【正确答案】
C
【答案解析】[解析] 细节题。答案在文章第一段：It has been demonstrated that rats will，when given a choice over a period of time，prefer water with vitamins to water without vitamins even though there is no difference in taste or smell between the two water bottles．
单选题
The expression "the habit" (paragraph one, sentence four) refers to drinking water which ______. A. has no smell B. is tasteless C. has vitamins D. is flavored
【正确答案】
D
【答案解析】[解析] 细节题。第一段最后谈到：“When a fragrant flavor was added to the vitamin—enriched fluid，the rats did seem to develop a taste for it and kept drinking it…”所以句子中的habit实际上指的是老鼠喜欢喝有香味的水。所以D是正确答案。
单选题
According to the passage, adults eating habits differ from those of babies because ______. A. adults know better than babies what kind 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
【正确答案】
C
【答案解析】[解析] 细节题。文章第二段的最后一句：“Babies managed to select well—balanced di—et．”，以及文章的第三段提到的“Many of our food preferences are culturally determined and influenced by long-established habits，”因此成年人和婴儿的饮食习惯的不同点在于：成年人的饮食习惯和他们的社会和文化习俗有关。
单选题
The author implied in the passage that most of us ______. A. eat a balanced diet B. choose the food that is of nutrition C. have the habits influenced by the surroundings D. like to eat the food with a fragrant flavor
【正确答案】
C
【答案解析】[解析] 细节题。根据上下文，我们可以知道．文章中并没有提到大多数人都有合理的饮食，选择有营养的食物以及喜欢吃有香味的食品。因此A、B、D都是错误的。但是文章的最后一句话说：“what people eat and how much they eat seems to be greatly influenced by what is going on around them．”因此可以断定：我们的饮食习惯受周围环境的影响。C是正确答案。
单选题
As far as their eating habits are concerned, babies and rats are similar in that ______. 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
【正确答案】
A
【答案解析】[解析] 细节题。文章第二段的最后一句话说Babies managed to select well—balanced diet，第三段的第一句话说：So，in selecting food，rats and babies do seem to know and act on what’s best for them．Apparently，there is a kind of body wisdom which humans soon lose．因此可以推断：婴儿和老鼠饮食习惯的相同点在于他们都会选择合理的饮食。因此只有A最符合题意。