- Mon Aug 19, 2013 5:44 pm
#10369
Good job on the negations - that's exactly the way I would have done them. Now it's just a matter of understanding the impact of those negations, and on that point I would have to disagree with you about the negation of answer choice B - I still say it has no impact.
Take a look at the author's evidence in support of her conclusion, which is that we should implement a smart highway system. Notice that traffic lights are not an element of her argument - she focuses instead on drivers having good, up to date information about alternate routes and where congestion is. Even if coordinated traffic lights would not assure free flow of traffic, her argument still sounds pretty good - informed drivers could make decisions that reduce congestion and thereby save money and improve productivity.
When we negate C, we find out that improvement is impossible. What does that do to the claim that we should implement the system? Completely destroys it - there's no point in implementing such a system if we cannot get any improvement as a result. The correct assumption answer, when negated, will typically obliterate the conclusion, either by directly contradicting it or by removing all of the supporting evidence for it. C fits that bill nicely, and so must be the correct answer.
There's one more way to look at this, and that's to remember the instructions for the LR section, which tell you to pick the BEST answer, not the "right" answer. Even if you read the negation of B as having some weakening effect on the argument, is it as strong an effect as that produced by the negation of C? Not even close. For that reason, C is the best answer (and that's how the authors of this test cover their backsides).
Adam M. Tyson
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