【正确答案】 A

【答案解析】[听力原文] Vitamin D is an essential vitamin required by the body for the absorption of calcium, bone development, immune functioning and alleviation of inflammation. Vitamin D comes from the sun and from some foods like nuts, lentils and fatty fish. Researchers have found that low levels of vitamin D could be related to dementia and Alzheimer's disease, one of the most common forms of dementia. Alzheimer's disease can be exhausting for caregivers and frightening to those who have it. People with Alzheimer's disease said 'The worst thing that I found was I was getting lost in the car, not just forgetting where I was going, I wouldn't know where I was. ' The World Health Organization estimates that more than 47 million people suffer from dementia, with about 60 percent of them in low and middle income countries, countries with the least ability to cope. U. S. researchers studied older adults and measured both their vitamin D levels and their cognitive ability, that is, the ability to remember things and to process thoughts. Some of the subjects had outright dementia, some had mild cognitive impairment and some had what we would call normal cognitive functioning. The researchers found that about 60 percent of the group was low in vitamin D. Those who had dementia also had lower vitamin D status than those who had mild cognitive impairment or who had normal cognitive functioning. Those low in vitamin D showed more short-term memory loss, as well as less ability to organize thoughts and make decisions. They were declining about two-and-a-half times faster than those who had adequate vitamin D. While this study shows that vitamin D seems to play a role in slowing the onset of dementia, more studies are needed to see if vitamin D supplements can help slow this decline. What can we know about Vitamin D according to the lecture? 听力原文中提到Vitamin D is an essential vitamin required by the body for the absorption of calcium...，由此可知，维生素D是身体吸收钙质所必需的，故选项A为答案，其他三个选项均与原文内容相反。

【正确答案】 A

【答案解析】[听力原文] What do we know about dementia according to the lecture? 听力原文中提到The World Health Organization estimates that more than 47 million people suffer from dementia, with about 60 percent of them in low and middle income countries...，即世界卫生组织预计，4700多万人患有痴呆症，其中大约60%来自中低收入国家，故选项A符合原文，为答案。其他三个选项与听力原文内容不符。

【正确答案】 C

【答案解析】[听力原文] What do the studies by U. S. researchers suggest? 听力原文中提到Those low in vitamin D showed more short-term memory loss, as well as less ability to organize thoughts and make decisions. 由此可知，维生素D 含量低的人表现出短期记忆力缺失以及在整理思绪和做决策等方面能力的不足，C项表述与之相符，故为答案，其中的less capable of是对原文中less ability to 的同义复现。其他三个选项均与原文的内容相反，可排除。