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PrepTest 73, Logical Reasoning 1, Question 15


Question 15, when a question asks for the criticism that an argument is most vulnerable to, then we have a flaw question. And our job one for question is to figure out what the error is in the argument. But of course, before we can figure out the error in the argument, we need to understand the argument which means understanding its conclusion and its evidence.

The conclusion of this argument comes at the very end, helpfully flagged by the conclusory keyword, thus. Thus, the advertising campaign was ill conceived. Now, the first sentence establishes what advertising campaign we're talking about. And also, it establishes that the consultant here thought that it wouldn't do so well.

There was an ad campaign for LRG, and the marketing consultant said, it's probably not gonna do so hot. The second sentence, well, the first half of it establishes that there was another consultant and LRG ignored the first consultants predictions and took the advice of the second consultant. And then finally, the third thing we learned is that sales are down it LRG, both old products and new products, particularly new products.

And that's why our marketing consultant says that the advertising campaign was ill conceived. So what is wrong with this argument? Well, basically the problem is a version of causation versus correlation flaw. We know the sales went down right after the ad campaign was put in the place. Which is to say, the two events are correlated, but just because two things happen at the same time or near in time to each other doesn't mean that one causes the other, correlation does not prove causation.

So that's the flaw we're gonna be looking for in the answer choices. Look at answer choice A. It takes for granted that LRG's sales would not have been lower still in the absence of the competitor's advertising campaign. This either choice fools a lot of people, but it is not our answer. It is true that in making this causation versus correlation error, the argument is assuming that without the plan, the sales wouldn't have gone down, but notice that this answer choice doesn't say without the plan, it says, without the competitor's advertising campaign.

That's not what happened here. LRG didn't ignore the consultant's plan in favor of a competing plan. There was just the one plan. LRG refused to listen to the first consultant's advice about the plan, and they listened to the second consultant's advice instead. There aren't two competing plans here.

There's competing advice about the plans. And that's why A is not our answer. Now if you go to answer choice B, fails to consider that economic factors unrelated to the campaign may have caused the low sales figures. Well, this is the correlation versus causation thing. It's failing to consider that maybe other things could have been responsible for the decrease in sales, it doesn't have to be the plan.

There could be other economic factors. So as choice B points out the correlation versus causation flaw, it is our answer. What's wrong with the other answer choices? Well, answer choice C is about what LRG should do or actually about what new products should do, know that this author never takes any stance on what LRG or anyone else ought to do.

They're just trying to describe what happened in this case. So what should happen is not part of this argument, so it can't be the flaw in the argument. Now, answer choice D, it's about the relationship between the new products and the established products. It's giving you reason why the established products are selling better.

That's not really a part of this argument. Why one's doing better than the other, doesn't matter. What matters is, is the overall decrease in sales related or not related to this new ad campaign. So D is not what we're looking for and then E, E's a sufficiency versus necessity flaw, which is a very common flaw on the test.

It's just not happening here. Nothing the author ever says relates to something being required or necessary. So while a common flaw, it's not happening here. Now answer choice B is our answer.

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