题目内容：

A disease called “Panama” is threatening supplies of the world's most popular fruit—banana.Two years ago,the United Nations warned that the "Panama disease" could destroy "much of the world's banana crop."Since then,things have not gotten better.A new outbreak was discovered last year in Australia.The disease started in Asia in the 1990s, and later spread to Africa and the Middle East.

World health officials worry the disease could travel to Latin America,one of the top banana producers in the world.All this is a big concern because bananas are an important source of income and nutrients for millions of people.They are grown in 135 tropical nations.The United Nations lists bananas as one of the most important foods, along with rice,wheat and corn.

Randy Ploetz is a professor at the Tropical Research & Educational Center at the University of Florida.Many consider him as America's top banana expert.As he explained,Panama disease affects the Cavendish banana.The Cavendish is one of more than 500 kinds of bananas.But it is the most popular.

“The industry is waking up to the problem,”Ploetz said.“They are pretty scared.”He was speaking Thursday by telephone from Miami,Florida,where he is among 1,000 people attending the International Banana Congress.The meeting was supposed to take place in Costa Rica,but was moved at the last minute.There were concerns banana growers could spread Panama disease from dirt collected on their shoes,Ploetz said.

Ploetz said reports that Cavendish banana production could end are not correct.But if the disease spreads to Latin America,it could hurt the world’s economy along with food supplies for millions of people.Still,he said there is reason for hope.Scientists in Australia are working on a genetically engineered banana that might not be at risk of getting Panama disease.

1.What makes World health officials worried about the disease?

A. Making the banana disappear.

B. Spreading to another continent.

C. No effective medicine to kill it.

D. No ways to stop it spreading.

2.What do you know about professor Randy Ploetz?

A. He is the best scientist studying banana in America.

B. He helps farmers grow various bananas.

C. He found more than 500 kinds of bananas.

D. He will find a better way to protect bananas.

3.What’s the possible measure to defeat the disease?

A. Using clone technology to kill the disease.

B. Inventing new medicine to prevent the disease.

C. Looking for effective ways to make banana healthy.

D. Developing a new type of banana free of the disease.

4.What can be a suitable title for the text?

A. Scientists Try to Protect Banana Trees.

B. Disease Spreads Quickly to Latin America.

C. Disease Threatens World Banana Supplies.

D. Banana Plays an Important Role in Economy.