【正确答案】 D

【答案解析】[听力原文]29-31
Why do we need a space station? Couldn't we do all those science experiments here on Earth. After all, the Space Station is expensive, and living in space can be dangerous. One of the answers has to do with gravity.
Scientists learn about things by doing experiments. Imagine you are a scientist who wants to understand how sunlight affects plants. You would do an experiment by putting one plant in bright sunlight and another plant in a dark room. Then you would watch them over several weeks and see what happens to the plants. Or maybe you wonder how gravity affects plants. You would put oneplant in a room with normal gravity, and another in a room with no gravity. But wait a minute! There is no such thing as a no-gravity room on Earth.
But the Space Station has them!
Everything is weightless on the Space Station. That makes it a great laboratory for studying the effects of gravity. Scientists do the same experiments on the ground as on the Station. They know that any differences are caused by gravity.
We already know that some chemicals combine differently in zero-gravity. Some physical things are different, too. Fires bum differently and fluids don't flow in the same way as on Earth. Even our bodies change without gravity. Station researchers can study many different areas, like biotechnology, biomedicine, fluid physics, and so on. They can make quite a list!
Question 29: What is the main idea of this passage?

文章围绕建立太空站的原因进行了阐述。因此正确答案是D。

【正确答案】 C

【答案解析】[听力原文]
What does the passage mention as one of the reasons of having a space station?

整篇文章都在探讨这个问题：主要是因为科学实验的需要。更具体地说是研究地球引力对生物影响的需要。据此可以选出答案是C。

【正确答案】 A

【答案解析】[听力原文]
All of the following EXCEPT which，mentioned by the passage，could be aided by the study on a space station?

根据最后提到的内容，可知答案是A。