gwd5-30

The irradiation of
food kills bacteria and thus retards spoilage. However, it also lowers the nutritional
value of many foods. For example, irradiation destroys a significant percentage
of whatever vitamin B1 a food may contain. Proponents of irradiation point out
that irradiation is no worse in this respect than cooking.  However, this fact is either beside the
point, since much irradiated food is eaten raw, or else misleading, since___

A. many of the
proponents of irradiation are food distributors who gain from food’s having a
longer shelf life

B. it is clear
that killing bacteria that may be present on food is not the only effect that
irradiation has

C. cooking is
usually the final step in preparing food for consumption, whereas irradiation
serves to ensure a longer shelf life for perishable foods

D. certain kinds
of cooking are, in fact, even more destructive of vitamin B1 than carefully
controlled irradiation is

E. for food that
is both irradiated and cooked, the reduction of vitamin B1 associated with
either process individually is compounded

这题最开始做的时候选了Ｃ，并且看了lawyer大牛的解释。

后来在网上找到一些相关资料，有了不同的想法。引用如下：

conventional familiar processes such as
cooking, drying, or freezing. Irradiation has no significant effect on the nutritional value of the macronutrients
within foods

现在倾向选Ｅ；cooking只是传统烹饪方法之一，Ｅ结合了二种方法（单独任何一种都有少量的Ｖ流失），结果会比任何其一要大；

Ｃ项，我理解是，其实想表达和Ｅ一样的内容，只是不够直接。whereas irradiation
serves to ensure a longer shelf life for perishable foods，虽然它的目的是想保存久一些，但是最终结果还是cooking（or other processes）---cooking is
usually the final step in preparing food for consumption