Question 22 is based on the passage you have just heard.

​​​​​​​听力原文

    Thanks to the International Space Station, we know quite a bit about the effects of low gravity on the human body, (22) [but NASA scientists want to learn more. To that end, they have been studying how other species deal with low gravity,] specifically focusing on mice. The results are both interesting and humorous.

    The scientists first sent some mice in a specially designed cage to the International Space Station. The cage allowed them to study the behavior of the mice remotely from Earth via video. As you’ll notice in the video, (23) [the mice definitely seem uncomfortable at the beginning of the experiment.] They move around clumsily, drifting within the small confines of the cage and do their best to figure out which way is up, but without success. However, it’s not long before the mice begin to catch on. They adapt remarkably well to their new environment and even use the lack of gravity to their advantage as they push themselves around the cage.

    That’s when things really get wild. (24) [The 11th day of the experiment shows the mice are not just dealing with the gravity change but actually seem to be enjoying it.] Several of the mice are observed running around the cage walls.

    The scientists wanted to see whether the mice would continue doing the same kinds of activities they were observed doing on Earth. (25) [The study showed that the mice kept much of their routines intact, including cleaning themselves and eating when hungry.] 

22. What do NASA scientists want to learn about?

解析：D。录音开头提到，我们知道了许多关于低重力对人体的影响。但是NASA（美国国家航空航天局）的科学家还想了解更多。为此，他们一直在研究其他物种是如何应对低重力情况的。由此可知，NASA的科学家想了解动物是如何应对失重的。D项内容与此表述一致，其中animals是对录音中other species的同义替换，deal with lack of gravity对应录音中的deal with low gravity，故正确答案为D。

错项排除：录音开头提到了human body和mice，但录音说的是，关于低重力对人体的影响，我们有了相当多的了解，而科学家还想知道的是老鼠如何应对低重力，而不是已知的低重力对人体的影响或者是老鼠如何模仿人类在太空中的行为，故A、B两项错误。录音中间部分提到了new environment，但此处说的是老鼠可以很好地适应新环境，并不是说科学家想了解老鼠如何在新环境中交流，故C项错误。