Dear honchos,

I'm happy to help with this.

First of all, here's a blog article on this question type:
http://magoosh.com/gmat/2012/gmat-logic ... -argument/

There's not really a quick-fix strategy for these, other than critical thinking and careful reading. One thing that helps is paying attention to all the "logic" words of the argument: "therefore", "since", "because", "although", etc.

Here' the last, incomplete sentence of that argument:
But this change is unlikely to result in a significant reduction in the number of fires caused by children playing with lighters, because children given the opportunity can figure out how to work the safety levers and ………..
I've highlighted the "logic" words. The initial "but" indicates a sharp contrast with the previous sentence, and this is consistent with content. First sentence --- manufacturers try to solve a problem by introducing safety levers --- then contrast --- BUT, this doesn't solve the problem.

Then we get the "because", and then reason #1, and then the word "and", which indicates we need another, parallel reason --- that is to say, another reason why introducing safety levers to lighters will NOT solve the problem of children playing with them & starting fires. Which answer choice could be another reason why introducing the safety levers will not solve the problem of kids playing with fire & burning houses down?
(A) economic, irrelevant
(B) this could be an additional reason, that would work well with reason #1
(C) has nothing to do with the introduction of safety levers
(D) the opposite of what we want, something that makes the lighters with safety levers more safe
(E) data from before safety levers were introduced, irrelevant

Pay attention to logic words always in GMAT CR. These subtle "signposts" make all the different in the flow of the argument, and in "complete the argument" CR questions, they are absolutely crucial for identifying precisely what you need in the blank.

Does this make sense?
Mike
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It is a long time I do not do simil.ar reasoning for a question. Maybe because my mind goes in auto mode :D
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This question is asking for an additional reason why the safety levers are unlikely to result in a reduction of the fires caused by children. The argument already provides one reason - that the children can figure out the safety levers so now we need to make it more likely that they will be able to start fires. Answer choice B says that not only will they be able to work the lighters but also will have access to the lighters - therefore the safety levers will make little difference in the number of fires.
Answer A only talks about expense which does not relate to the likelihood of fires
Answer C does not address stopping children from starting fires, only that the fires can be quickly extinguished
Answer D actually goes opposite of the argument, showing that there could be a reduction because children under 2 could not start fires.
Answer E only tells us the number of fires, does not discuss whether children will be able to start the fires.


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Argument Construction

Situation Manufacturers must equip all cigarette lighters with child-resistant safety levers, but children can figure out how to circumvent the safety levers and thereby often start fires.

Reasoning What point would most logically complete the argument? What would make it likely that the number of fires caused by children playing with lighters would remain the same?

In order for children to start fires using lighters equipped with safety levers, they must be given the opportunity to figure out how the safety levers work and then to use
them. They must, that is, have access to the lighters.

A If safety-lever-equipped lighters are more expensive than lighters that are not so equipped, fewer lighters might be sold. This would most likely afford children less access to lighters, thus giving them less opportunity to start fires with them.

B Correct. This statement properly identifies a point that logically completes the argument: it explains why children are likely to have access to lighters equipped with safety levers.

C The speed with which fires are extinguished does not have any bearing on the number of fires that are started.

D This provides a reason to believe that the number of fires started by children will most likely decrease, rather than stay the same: fewer children will be able to operate the lighters, and thus fewer fires are likely to be started.

E This information about how many fires were started by children before safety levers were required does not have any bearing on the question of how many fires are likely to be started by children now that the safety levers are required.

The correct answer is B.
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