The United States government wants to know what the public thinks about its findings on the safety of cloned animals.

The Food and Drug Administration says meat and milk from clones of adult cattle, pigs and goats are safe to eat. An F.D.A. official called them "as safe to eat as the food we eat every day." And when those clones reproduce sexually（有性繁殖）, the agency says, their offspring（后代） are safe to eat as well. But research on cloned sheep is limited. So the F.D.A. proposes that sheep clones not be used for human food.

The United States this year could become the first country to approve the sale of foods from cloned animals. First, however, the public will have ninety days to comment on three proposed documents. On December 28th the F.D.A. released a long report, called a draft risk assessment, along with two policy documents.

The agency says it must receive comments by April second. The F.D.A. seemed ready to act several years ago, but an advisory committee called for more research.

For now, the government will continue to ask producers to honor a request that they not sell foods from cloned animals.

Clones are still rare. They cost a lot and are difficult to produce.

The F.D.A. says most food from cloning is expected to come not from clones themselves, but from their sexually reproduced offspring. It says clones are expected to be used mostly as breeding animals to spread good qualities.

Public opinion studies show most Americans do not like the idea of food from cloned animals. But this research also shows the public knows little about cloning.

Cloning differs from genetic engineering. A cell taken from a so-called donor animals is grown into an embryo（胚胎）in the laboratory. Next, the embryo is placed into the uterus（子宫）of a female animal. If the process is successful, the pregnancy reaches full term and a genetic copy of the donor animal is born.

13. From the passage we know that .

A. foods from cloned animals are popular in America

B. cloned adult animals are safe to eat except sheep.

C. cloned animals will be easy to produce

D. most foods from cloning is expected to take place of other foods

14.The main purpose of the text is to .

A. tell a interesting story B. give some advice on foods

C. give a report D. compare different opinions

15. Who believe that foods from cloning are safe to eat?

A. Most Americans B. An advisory committee

C. Critics D. The F.D.A.

16.It can be inferred from the last paragraph that .

A. cloning has much in common with genetic

B. not every cell taken from a donor animal can grow into a genetic copy

C. the donor animal should be a female one

D. cloned animals grow faster than normal ones

答案及解析：

13.B.推理判断题。从文中第二段可推出。

14.C.主旨大意题。本篇文章是关于克隆食物的安全问题的报道。

15.D.事实细节题。从“The Food and Drug Administration says meat and milk from clones of adult cattle, pigs and goats are safe to eat.…”可知。

16.B. 推理判断题。从最后一段“If the process is successful, the pregnancy reaches full term and a genetic copy of the donor animal is born.”可知答案。