单选题
You will hear three dialogues or monologues. Before listening to each one, you will have time to read the questions related to it. While listening, answer each question by choosing A, B, C or D. After listening, you will have time to read your answer. You will hear each piece once only.

Questions 11-13 are based on the following talk about the Space Shuttle Columbia. You now have 15 seconds to read Questions 11-13.

【正确答案】 A

【答案解析】[听力原文] 11-13 The first flight of the Space Shuttle Columbia in the spring of 1981 was a revolutionary development in space exploration. Unlike the rockets of the previous twenty years, Columbia has the enormous advantages of being specially designed to return to earth and make further flights. Among a large number of projects scientists are investigating its future use. The most exciting, perhaps, is that the first steps can now be taken towards establishing human colonies in space. The present Space Shuttle can only stay in space for about a week, but it could take people out to build "islands" where they stay for longer periods. By the year 2050 scientists estimate that man will be able to construct permanent settlements. The first "islands" would be energy stations. There would be no hope of establishing colonies in space unless people could obtain energy there, instead of getting it from the earth. However, if the original could convert solar energy into electricity, it would be possible to provide the equivalent of a filling station for cars on earth, allowing the Space Shuttle to refuel and stay in orbit for longer periods of time. If this initial project were successful, much larger solar energy stations would be constructed later with materials brought out by the Shuttle. Eventually, man would be able to construct an "inhabitable planet" in space.

A、 Because it is not similar to the spaceships of the previous twenty years.
B、 Because it has different designs and is able to return to earth and make further flights.
C、 Because it can be used in a variety of ways now.
D、 Because it can be used to establish colonies on earth.