Okay, let's take this baby down. Some explanations in this forum focus exclusively on how to answer specific, isolated questions. But remember:
the GMAT is a critical-thinking test. For those of you studying for the GMAT, you will want to internalize strategies that help you to identify and solve entire classes of questions.
Pattern recognition is key. The tactics I will show you here will be useful for numerous questions, not just this one. This solution is going to walk through not just what the answer is, but how to strategically think about it. Here is the full "GMAT Jujitsu" for this question:
This problem highlights a common tactic of the GMAT: trying to hide what type of question it actually is. In this case, the question stem is vague enough you can’t really tell what problem type it is. At first glance, the phrase "
most logically completes the argument" makes this sound like the question is looking for a conclusion, but this is
not the case at all. We must fill in the blank. With such “
Fill in the Blank” type questions, there is a strategy that helps you to identify the problem type. I call this “
Find the Flow” in my classes. In the original problem, you can see that the stimulus ends with an underlined portion, preceded by the word “
since.” “
Since” is a type of leverage word I call a “
Conclusion Conjunction.” While such words are directly attached to the conclusion, they actually precede a premise used to support the conclusion. Thus, when the stimulus says, “
This fact… is misleading, since _____”, our conclusion is “
the fact is misleading”, and the phrase that fills in the blank is a supporting premise. Remember: premises support conclusions.
Since we are looking for a missing premise, we know that this is a “
Strengthen” question type. This defines our strategy, because it tells us we are looking for an answer choice that strengthens or justifies the conclusion. We need to focus on what the problem is asking. In this case, we are looking for a statement that explains why the statement “
irradiation is no worse in this respect than cooking” is actually “
misleading.” That becomes the logical gap on which we need to focus.
Let’s look at the answer choices, “
minding that gap.”
Answer choice “A” falls to connect the logical dots. Talking about the motives of “food distributors” is a classic
ad hominem attack. It attacks the potential motives of the proponents of the food distributors instead of focusing on the actual logic. "A" does nothing to explain why it would be "
misleading" to say that irradiation is the same as cooking.
Answer choice “B” tries to use your own biases against you. A beautiful trap with this question is that it tempts your brain to start filling in extra information. Some test takers see the word “
irradiation” and start thinking of nuclear bombs and mutant, three-headed dogs (arguably making irradiation “
worse than cooking.”) But such effects are not mentioned in the question stem. And, even if they were, the focus of the question is on why it is misleading to say that irradiation is no worse than cooking when it comes to lowering the nutritional value of foods. Other possible effects that are unrelated to lowering the nutritional value are irrelevant here. In my classes, I call these types of traps "
Distracting Detours" because such answer choices not only make us imply extra information not specifically mentioned in the question but also get us focused on other things besides the specific logical gap. Answer choice “B” can be eliminated.
Answer choice “C” also fails to mind the logical gap. The fact that cooking and irradiation serve different purposes doesn’t explain why irradiation is somehow worse than just cooking. This doesn’t show the proponents’ claim is "
misleading."
Answer choice “D” goes the opposite direction of what we want (another classic GMAT fake-out.) It tells us that some cooking is “
more destructive” than irradiation. But we are trying to undermine the phrase “
irradiation is no worse than cooking”. Answer choice D gives us a reason why “
cooking” is worse than “
irradiation”, not vice versa. Get rid of “D”.
Answer choice “E” shows how irradiation could be worse than cooking – because if you cook something irradiated, the loss of vitamin B1 is “
compounded.” It minds the gap and shows why the statement “
irradiation is no worse than cooking” is "
misleading."
Answer choice “E” is our answer.Now, let’s look back at this problem from the perspective of strategy. This problem can teach us several patterns seen throughout the GMAT. First, when a question requires you to "Fill in the Blank," find the flow of the logic. Premises support conclusions, which helps you to identify the direction (or flow) of the information. Then, once you identify the structure of the problem, focus
EXACTLY on what the problem is asking. Many people miss Critical Reasoning questions because they rush too quickly through the interpretation of the question and miss crucial leverage words. In the case of this problem, we are looking for an answer that shows why the argument that "
irradiation is no worse...than cooking" is "
misleading." Focusing on the exact logical gap keeps us from falling for distracting traps and detours.