题目内容：

    Antaretica’s ice-white environment is going green and facing other unexpected threats. Scientists say that as temperatures go up in the polar region, invading (入侵) plants and insects, including the flies, cause a major conservation threat.

More and more of these invaders, in the form of larvae (幼虫) or seeds, are surviving in coastal areas around the South Pole, where the temperature has risen by more than 3℃ over the past three decades. Glaciers have retreated, exposing more land which has been occupied by mosses that have been found to be growing more quickly and thickly than ever before-providing potential green homes for invaders.

“The common house flies are a perfect example of the problem the Antarctic now faces from invading species,” said Dominic Hodgson of the British Antarctic Survey. “It comes in on ships, where it exists in kitchens and then at bases on the continent. It now has an increasing chance of surviving in the Antarctic as it warms up, and that is a worry. Insects like the house flies carry bacteria that could have a deadly effect on native lifeforms.”

The Antarctic has several native species of insects. Together with its native mosses, these are now coming under increased threat from three major sources: visiting scientists, increasing numbers of tourists and global warming. However, it is global warming that is the main driver of the greening of Antarctica.

In 2015, more than 38,000 tourists visited Antarctica. “These tourists are often very careful about not leaving waste or having mud. But they could carry seeds or larvae on their boots when they set foot on the Antarctic,” said Hodgson.

More and more invasive insects and plants have been found on the Antarctic and have required removal. “the insects and plants that are native to Antarctica have survived these for thousands of years,” said Hodgson. “We have got to act now if we want to save the environment.”

1.What does the underlined world “mosses” in paragraph 2 refer to?

A. A kind of plants    B. House flies

C. Coastal areas    D. A kind of animals

2.What is the main cause of the Antarctic going green?

A. Scientists’ coming.    B. Global warming.

C. A growing number of visitors    D. The rapid spread of native planting.

3.What do we know about the house flies in the Antarctic?

A. They are native to the Antarctic.

B. They will disappear due to the cold climate.

C. They seriously affected the Antarctic native species

D. They directly fly to the Antarctic from nearby islands.

4.What’s the best title for the text?

A. The Antarctic Is Faced with Various Threats

B. The Antarctic Is Becoming Green and Energetic

C. More and More Scientists Get to Explore the Antarctic

D. Global Warming has Caused the Temperature in the Antarctic to Rise up