CEdward wrote:
Need expert's help (any anybody else too for that matter).
On the GMAT, a choice that introduces an idea suggesting that a plan will lead to another problem (A) in this example) can be correct. How do we distinguish between those choices and shell-game answers (that are incorrect)?
GMATNinja AndrewNHello,
CEdward. As LSAT logical reasoning questions go, I thought this was one of the more straightforward ones, akin to a GMAT™ CR question. I have heard the term
shell-game answer in reference to the CR Bible, so if you have that resource, you should have plenty of insight into your own question. Regarding my own approach to CR passages, and to answer your question in my own way, I always look to follow what I call the
linear logic, and I keep my thoughts centered on the question itself. In this case, to
weaken the argument, we need to be able to identify
exactly what that argument may be. To put it simply, the logging industry official says that harvesting old-growth trees reduces carbon dioxide in the atmosphere. The first sentence puts forth the claim and offers support for it in the
since clause, although we have to understand that harvested trees are
removed from the forest for the pieces to fit; the second sentence offers further support—notice the transition
moreover. To weaken the argument, then, we need to attack this notion that harvesting old-growth trees necessarily reduces levels of carbon dioxide in the atmosphere.
Choice (A) is an unrelated concern. Unless
animal species can in some way be tied into the atmospheric carbon dioxide cycle, we cannot make heads or tails of the information presented. For this sort of answer to be correct, the question frame would need an adjustment, and that is the best answer I can think to give to your query. Read the passage, question, and answer choices carefully before you commit to anything, and focus on disproving answers as you comb through the options.
Meanwhile, choice (B) is the only one that attacks the heart of the argument. If the
organic matter from harvested old-growth trees—the same trees on which the argument is based—that is
not turned into lumber is
made into products that decompose rapidly, then from what the passage tells us in line one, we would expect such decomposition to contribute to
increasing carbon dioxide in the atmosphere, regardless of the net change. (Yes, the argument could still hold, but this new consideration allows us to appreciate that the picture might not be as grim as the one outlined in the passage.)
That is as far as I took my thoughts on these two answers. I hope the above analysis may prove helpful to you. Thank you for thinking to ask.
- Andrew
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