What is the main finding of a new study about many Americans?

关于许多美国人的一项新研究的主要发现是什么?

A)他们现在不如以前那样关心自己的饮食了。

B)他们可能对健康食品缺乏足够的了解。

C)他们可能对自己的饮食持过于乐观的看法。

D)他们对食物的选择不够重视。

新闻开头就提到，许多美国人认为他们做出了健康的饮食选择，但他们可能对自己的饮食过于乐观了。这是位于密西西比州斯通维尔的美国农业部研究人员一项新研究的主要发现。由此可知，选项C为正确答案。其余三项新闻中均未提及，可排除。

Who tended to rate their diet more accurately in the survey?

在调查中，谁往往能更准确地对自己的饮食进行评级?

A)那些完成了24小时饮食问卷调查的人。

B)那些完全理解评级标准的人。

C)那些关心食品质量的人。

D)那些将自己的饮食评为“差”的人。

新闻末尾提到，这项新研究发现，在调查的9700多人中，大约85%的人在评估自己饮食的品质时是完全错误的，几乎所有人都高估了自己饮食的健康程度。那些将自己饮食评为“差”的人往往准确得多。由此可知，选项D为正确答案。

听力原文：

News Report Two

Many Americans think they make healthy food choices, but they may be viewing their diet too optimistically.That's the main finding of a new study by researchers at the U.S. Department of Agriculture in Stoneville, Mississippi.

The study aimed to identify disconnects between how healthily Americans think they eat and how they actually do. For the study, the researchers asked participants to rate their diet as excellent, very good, good, fair or poor. Folks also completed 24-hour food questionnaires. Then, the researchers compared answers to see how well responses to the two exercises matched up.

Of more than 9,700 people, roughly 85 percent were off base when asked to rate the quality of their diet, and almost all overestimated how healthy it was.  Those who rated their diet as poor tended to be far more accurate.Their rating match that of the researchers more than nine times out of ten.