题目内容：

Raising a baby takes a lot of work, especially when that baby is a king penguin. Now, it looks like climate change will make life even harder for these birds.

Most king penguins live on the Crozet Archipelago, a group of islands in the Indian Ocean, about 1，000 miles north of Antarctica. After the penguin chicks are born in November，which is summer in the Southern Hemisphere，both parents spend 4 months collecting fish to feed their offspring (后代)．

When the fish move to deeper waters in March, the adults swim hundreds of miles south.  There, near the Antarctic ice, they spend the winter eating seafood to add to their own energy stores. In October, the parents return to their babies and finish raising them.

Scientists from France have been studying king penguins for a decade. Starting in 1998，Yvon Le Maho and his colleagues put electronic ID tags under the skin of hundreds of penguins. These are the same types of tags you might put in your dog or cat so that you can track them if they're lost. The tags have allowed researchers to get everything about penguins, such as how long they live, whether they return from their winter trips, and if their babies manage to survive the winter.

To see whether water temperatures affect the penguins, Le Maho compared his data with temperature records.  Ocean surface temperatures vary from year to year. And previous research had shown that fewer fish and other creatures grow when the water is warmer. Le Maho suspected that this drop would make it harder for adult penguins to survive the hard times ahead. Indeed, his results showed that fewer adults survived during winters when the water was especially warm.

King penguins can live for up to 30 years. And for now, the population still appears healthy. But a warming trend could spell big trouble for a bird that depends on cold and ice.

1.What do adult penguins do in March?

A. They swim south to find food for their offspring.

B. They leave their offspring alone for months.

C. They take their offspring elsewhere to search for food.

D. They teach their offspring some living skills.

2.In the research, electronic ID tags were used to________．

A. help penguins recognize each other

B. help researchers tell one penguin from another

C. keep track of the details of the penguins

D. help researchers find the lost penguins

3.What attitude does the author hold towards the future of penguins?

A. Worried.    B. Optimistic.

C. Indifferent.    D. Satisfied.

4.What is the purpose of the passage?

A. To call on people to fight against global warming.

B. To call on people to protect the endangered penguins.

C. To tell global warming is threatening the survival of penguins.

D. To explain how global warming affects the life of sea animals.