Question 23 is based on the passage you have just heard.

Passage Three

听力原文

    Watching more than 3 hours of television a day doubles memory loss in older people, a new study of more than 3,000 adults suggests. (22) [Scientists at University College London used memory and fluency tests on the same group of people 6 years apart.] They found that those who watched on average less than 3 hours’ television a day showed a decline of around 4 to 5 percent, while those who tended to watch more than 3 hours a day declined by an average of 8 to 10 percent. (23) [The research team say they believe the “alert-but-passive” nature of television watching may be creating stress on the mind, which contributes to memory decline.]

    Older people who watch more television are also less likely to undertake activities known to preserve mental functioning, such as reading, or interactive screen-based pursuits such as using the Internet or playing video games. (24) [The researchers say that television viewing may be a risk factor for Alzheimer’s disease, but more research is needed to establish a link.]

    While watching television may have educational benefits and relaxation benefits, (25) [the researchers advise that adults over the age of 50 should try and ensure that television viewing is balanced with other contrasting activities.] If you’re concerned that the amount of television you’re watching could have a negative impact on your health, you should limit the amount of TV you watch each day and undertake some healthy hobbies.

23. What contributed to memory decline in the participants?

解析：A。在录音中，研究团队称，他们认为人在看电视时虽然思维活跃，但是属于被动思考，这可能会给大脑造成压力，从而导致记忆力减退。因此A选项符合题意。

错项排除：B项和D项利用录音中出现的using the Internet or playing video games作干扰，C项利用录音中出现的reading作干扰，但录音中说的是上了年纪的人如果花很长时间看电视，就更难进行可以维持大脑机能的活动，比如阅读或面对屏幕的互动行为（如上网或玩电子游戏），并未说阅读、上网或玩电子游戏等行为会导致记忆力减退，故排除B、C、D三项。