题目内容：

Millions of people die of hunger in southern Africa every year, but when Zambia was offered thousands of tons of free maize by the US, the government politely said no.

    “We don’t know whether the food is safe,” said Zambia’s commerce, Trade and Industry Minister Dipak Patel.

His worries are shared by countries around the world that are in two minds about America’s genetically modified（GM,转基因的）crops．Just last week, EU（欧盟）member nations were discussing whether or not to import GM sweet corn from the US．

Ever since people started farming, they have tried to crossbreed（杂交）plants to make them stronger or better tasting. At one time, only related plants could be crossed with each other．

But when GM techniques were developed in the 1970s, scientists were able to put a single gene from a living creature into an unrelated creature.

This means they can make crops more productive and resistant to disease by adding genes from other species．They can also create food with special characteristics, such as “golden rice”, which is enriched with vitamin A. But many people believe GM foods are a health risk.

At the moment, the official argument is that GM foods “are not likely to present risks for human health”. But there are still many questions to be answered as the foods are produced in different ways.

    Some experts believe the genetic material added to plants can transfer to humans and give damage to our bodies. Further harm could be caused by the genes from GM plants crossbreeding with naturally produced crops．

    People in China are also getting worried about GM foods. More than 70 percent of the

country’s soybean oil is produced from imported GM soybeans. Meanwhile, an investigation last November found that 12 of 60 famous foods sold across the country were GM products. The government has begun to introduce a marking system for GM goods so that people can choose whether or not to eat them.

1.Which is the best title for the passage?

A. Harmful GM foods                                 B. Advantages of GM foods

C. GM foods, a health risk?                            D. the Techniques of GM foods

2.Why has Zambia refused the American free maize?

A. they decide to follow EU member’s advice

B. they are concerned about the safety of GM foods

C. they care little about the problem of starvation  

D. they are too proud to accept free offer

3.It has been proved that _________.

A. GM foods are harmful to people’s health   

B. GM food is no better than naturally produced foods

C. only related plans could be crossed with each other

D. GM techniques can increase the production of crops

4.Which of the following statement is TRUE?

A. GM foods are a health risk.

B. Only Zambia worries about the safety of GM foods .

C. China’s government hasn’t taken any action about GM foods. 

D. Some experts believe human bodies can absorb genetic material from GM foods.

5.What’s the author’s attitude towards GM foods?

A. Supportive.        B. Neutral.         C. Doubtful.        D. Critical.