Question 23 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.] 

23. What does the passage say about the mice at the beginning of the experiment?

解析：A。录音中间说到，在实验开始的时候，老鼠显然不太舒服。由此可知，在实验开始时，老鼠是不习惯这种低重力环境的，故正确答案为A，其中not used to对是录音中uncomfortable的同义替换。

错项排除：录音中间提到了figure out，但此处说的是老鼠想尽办法想弄清楚哪边是朝上的，并没有说它们很难弄明白自己在哪里，故B项错误。录音中间说到了small confines of the cage，但这里是说老鼠在笼子狭小的空间里笨拙地移动着，并不是说笼子太小，无法待在里面，故C项错误。录音中说到，在实验一开始老鼠明显不太舒服，说明它们对变化的环境是敏感的，故D项错误。