【正确答案】 B

【答案解析】[解析] 18-20
Are organically grown foods the best food choices? The advantages claimed for such foods over conventionally grown and marketed food products are now being debated. Advocators of organic foods (a term whose meaning varies greatly) frequently proclaim that such products are safer and more nutritious than others.
The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs. Although most of these claims are not supported by scientific evidence, the preponderance of written material advancing such claims makes it difficult for the general public to separate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form the basis for folklore.
Almost daily the public is besieged by advocates of "no-aging" diets, new vitamins and other wonder foods. There are numerous unsubstantiated reports that natural vitamins are superior to synthetic ones, that fertilized eggs are nutritionally superior to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. As a result, many consumers are likely to buy organic foods which cost more than conventionally grown foods even though some of them have a very limited income.

文中关键句是“The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. ”

单选题 What can be concluded from the talk?
A. Consumers should buy organic foods if they can afford.
B. Natural foods should be advocated widely because they are both safe and nutritious.
C. In many cases consumers are misled in believing only organic foods are the best.
D. Conventionally grown foods are not nutritious as the organic foods.