题目内容：

More than 2.25 billion cups of coffee are consumed across the globe each day, and it’s likely that many taste bitter.

Now, a new study suggests that coffee fans can make their drink taste sweeter by simply changing the colour of their cups.

Scientists claim that blue and glass mugs, which are popular in some coffee shops, can reduce coffee’s bitterness, without any need for sugar, and that coffee drunk from white cups tastes the bitterest.

To prove their claims, the researchers invited 36 volunteers and used three different colored cups -- blue, white and transparent glass -- to do an experiment.

In the experiment, coffee consumed from the white cup was found to taste less sweet when compared to the other two colored cups, while the blue cup made the coffee taste the sweetest.

The scientists believe that the colour brown may be associated with coffee’s bitterness because coffee in a white cup appears the brownest and tastes the bitterest.

“Our study clearly shows that the colour of a coffee cup does influence the perceived (感受到的) taste and flavor of coffee,” said Dr George Doorn of Federation University Australia, “but the potential effects may be different between a one-time purchase and a return customer.”

“Anyhow, the effect of the colour of the cup on the flavor of the coffee suggests that café owners, baristas (服务员), as well as coffee cup manufacturers should carefully consider the colour of their cups, ” he added.

However, the idea that colour can alter the taste of food and drink is not new.

A study published last year revealed that red, strawberry-flavored mousse (慕斯蛋糕) served on a white plate was rated as 10 percent sweeter and 15 percent more flavorous than the same food presented on a black plate.

1. What color of the cup can best reduce coffee’s bitterness without adding sugar?

A. Blue.             B. Brown.         C. White.     D. Transparent.

2. The scientists used ________ to do the experiment to prove their claims.

① different brands of coffee

② different colored coffee cups

③ several volunteers

④ several manufactures

A. ① ②           B. ② ③         C. ② ④       D. ③ ④

3. Why does coffee in white cups taste the least sweet?

A. Because white cups are not as beautiful as other cups.

B. Because white cups make coffee appear the brownest.

C. Because white cups reduce the sugar in them.

D. Because white cups are better used to serve cakes.

4.According to the article, which of the following statements is TRUE?

A. Black plates increase the sweetness of food and drink.

B. Strawberry-flavored mousse is 10 percent sweeter than coffee.

C. People consume more than 2.5 billion cups of coffee across the globe every year.

D. People can make coffee taste sweeter by changing the color of their coffee cups.