Which of the following most logically completes the argument?
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

Please explain the meaning of the last line in the argument and then the options.

SOURCE: GMATPREP

Regards,
Phil

when you get one of these questions, you should try to simplify the argument as much as you can. once you do that - get rid of as much "noise" and verbiage as possible - you should be able to answer the questions more readily.

in this case, here's a more "noise-free" version of the argument:

People have compared irradiation to cooking and found that they're about the same (in terms of leaching nutrients). Why is this comparison misleading?

(note that you're ONLY concerned with the "misleading" part, since that's where the blank is. the "beside the point" part DOESN'T MATTER AT ALL.)

--

so, you're looking for a reason why it's MISLEADING to COMPARE IRRADIATION TO COOKING.

when you COMPARE two things, the assumption is that they are ALTERNATIVES.

therefore, if a comparison is "misleading", we need a choice that shows that they aren't simply alternatives.

this is what choice (e) does: it shows that some food is irradiated AND cooked. they're not alternatives, so you can't settle the issue with a comparison.

--

analogy:
let's say that dieting burns MORE body fat than does exercise, all other things equal.

if i say "you should just diet, since exercise is no better than dieting", then that's MISLEADING.

why is it misleading?
because ... you can do both, compounding the effects.

same deal here.

Ron:
What is wrong with Option C here ?
I see even this option is providing the same thing which we are getting from e.

the point of option (c) is to highlight the difference in timeframes: cooking is done directly before the food is eaten, whereas irradiation is performed when the food is going to sit on the shelf for a long time (i.e., not directly before the food is eaten).
that difference may be significant in some contexts, but it has nothing to do with why the stated difference between cooking and irradiation is “misleading”.