Question 24 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.

24. What did the researchers say about their finding concerning the link between TV viewing and Alzheimer’s disease?

解析：A。根据选项中多次出现的television viewing和Alzheimer’s disease，推测本题可能考查看电视与阿尔茨海默症之间的联系。在录音中，研究者称，看电视可能是导致阿尔茨海默症的一个风险因素（a risk factor），但还需要进行更多研究来证明两者之间存在联系。因此A选项符合题意，a potential factor是对a risk factor的同义转述。

错项排除：B项利用录音中提到的三小时看电视时间作干扰，但录音中说的是每天看三个小时以上电视的人平均记忆力衰退程度为8%至10%，并未说阿尔茨海默症患者往往一天看电视超过三小时，故排除B项。录音中提到，还需要进行更多研究来证明两者之间存在联系，并未说两者之间的联系已经得到证实，因此C项排除。录音中表示看电视可能是导致阿尔茨海默症的一个风险因素，说明看电视不会对阿尔茨海默症患者有益处，故D选项错误。