Doctor: Medical researchers recently examined a large group of individ

Breaking the argument down into a short summary.
Back Pain = BP, C = Bulging/Slipped Disks, P = The group of people examined.
1. a certain group P.
2. Common Belief - C --> BP.
3. After examining, 1/2 of P had C.
C Since 1/2 of P --> C ---> C -->No BP

Note here that the argument is open to the possibility of alternate factors for the condition in order to state that C is not the factor of BP.

Now that understanding the argument is out of the way, let's look at the answer choices.




Does the argument really fail to consider this? This talks about the sufficiency of the factor to cause the condition. Can one particular factor alone be enough to cause the effect? even in the absence of other factors that obviously could cause the condition? Once you try to examine this deeply, you'll arrive nowhere. Such options are definitely wrong. OUT



The factor - C isn't sufficient alone. But, could be one of the reasons to cause BP sometimes.
Yes! We know from the conclusion that all people who have back pain indefinitely have bulging/slipped discs, which were thought to be the causes of the condition in the first place. Now, when a sample of people who don't have backpain are examined and half of them, a substantial amount, are found to have Bulging/Slipped disks, we should be able to understand that bulging discs isn't the only cause. The Argument without even considering this however, goes on to conclude that the common view was wrong and bulging discs isn't a cause at all. It cannot explain the existence of these discs in the people who are affected by the condition. Hence, we can comprehend that among the other possible causes, bulging discs could be a cause too. CORRECT



The effect here is nothing but C, and the phenomenon is BP.
We know that C can exist when there is BP from the argument itself. OUT



This isn't a flaw. The Characteristic = C. C might not happen to the other half. We know this. OUT



incidence of C when BP happens > incidence of C BP doesn't happen. This is a comparison of when BP does and doesn't happen.. Well, we know from the argument that all BP affected people have C and half of the examined bunch have C. The argument doesn't fail to state this. OUT

If you're patient enough to read through, you'll be more than able to understand. This is a really HARD LSAT question so don't worry, you won't come across such a gnarly question.

However, I recommend that the moderators or Hovkial post the OE here for a better solution.

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