October 20, 2009

Homework #18 Answer

It is healthier to eat frozen vegetables than fresh ones. This is not because freezing makes them more nutritious. In fact, freezing actually causes food to lose some nutrients. Still, frozen vegetables are better for you because crops are usually harvested before they are ripe. Vegetables are at their most nutritious when they are allowed to ripen in the field. However, if they are picked when they are ripe, they would go bad by the time they reached the consumer. That's why they have to be picked early, and allowed to ripen in transit. These fresh vegetables never reach their full nutritional value. On the other hand, vegetables can be picked when they are ripe and then immediately frozen. As a result, frozen vegetables are generally more nutritious than the fresh vegetables we buy at the grocery store.

The above argument is based on which one of the following assumptions?

A. Frozen food companies freeze only the most nutritious kinds of vegetables.

(A) is incorrect because the argument stands even if this is not true. The argument is that frozen vegetables are ultimately better for you than fresh ones because the frozen ones are picked ripe and retain more nutrients than the fresh ones, which are picked early and have to ripen on the truck or in the store instead of on the vine. This distinction would remain regardless of which kinds of vegetables are being frozen.

B. Vegetables lose less nutrition from freezing than they do from being picked early.

(B) is correct. The stimulus acknowledges that both freezing vegetables and picking them early cause them to lose nutrients by the time they are sold, prepared and eaten. Yet the stimulus unequivocally states that frozen vegetables are "healthier," "better for you" and "more nutritious" than fresh ones. If they both lose nutrients along the way, then the only way one can be "better" than the other is if it loses less than the other. Therefore, the assumption must be that freezing vegetables is less harmful to their nutritional value than picking them early. If the opposite is true, or if they're the same, the argument falls apart.

C. Fresh vegetables are never sold immediately, but rather sit on shelves for a long time.

(C) is incorrect because whether this is true or not does not affect the author's claim. The argument is that fresh vegetables lose nutrients because they are picked early and have to ripen on the truck or in the store instead of on the vine. This is still a valid argument whether they are "sold immediately" or not.

D. People never freeze the fresh vegetables they buy at the grocery store.

(D) is incorrect because what people do with the vegetables after they are purchased is not part of the argument. The author is concerned with what happens to the nutritional value of vegetables between the time they are picked and the time they reach the consumer. His argument in favor of frozen vegetables over fresh ones remains valid regardless of what happens outside of this time frame.

E. All kinds of vegetables ripen at about the same rate in the same amount of time.

(E) is incorrect because the author does not attempt to distinguish the ripening characteristics of different vegetable varieties. Even if different kinds ripen faster or slower than others, the argument remains valid that more nutrition can be preserved by freezing ripe vegetables than by picking them early and letting them ripen on the way to the store.