Q19 - Doctor: The patient had been experiencing back and leg

[ohthatpatrick]

Question Type:
Necessary Assumption

Stimulus Breakdown:
Conclusion: The pressure on that nerve was causing the patient's back/leg pain.

Evidence: If there was pressure on the nerve pain, it would be inflamed, and cortisone injection would be the best way to reduce inflammation. I gave the patient a cortisone injection and this decreased the pain.

Answer Anticipation:
Given all the Evidence, how could we still argue that the source of the pain WASN'T pressure on that nerve? We could say the pain was being caused by something else, and the cortisone injection just managed to quell that pain somehow.

Correct Answer:
C

Answer Choice Analysis:
(A) Extreme (red flag): "the most accurate way". It doesn't do anything to this argument if computer scans are the 2nd most accurate way.

(B) This seems opposite of what the author thinks. She thinks that pressure -> inflammation -> pain, and that cortisone got rid of the inflammation, which got rid of the pain. The cortisone may or may not have also gotten rid of the pressure that caused the inflammation, but the author's argument would be the same either way. The negated version of this is that "the cortisone injection DID reduce pressure on the inflamed nerve". Would that badly weaken the author? No, it sounds like it goes along with the author.

(C) YES, this works. This rules out an alternate cause for the pain relief. If we negate it, it badly weakens the argument: "the pain relief occurred merely because the patient believed in the efficacy of cortisone", so therefore the effectiveness of the cortisone treatment is no evidence that the author was correct about the source of the patient's pain.

(D) Extreme (red flag): "ONLY cortisone injections can reduce inflammation". The author isn't assuming that. She says that cortisone is the best way to reduce inflammation, not the only way.

(E) Extreme (red flag): The BEST treatment is USUALLY anti-inflammatory drugs? This argument is only about this patient and his diagnosis. The author doesn't need to assume anything about what is the best treatment in over 50% of cases.

Takeaway/Pattern: If we only had 15 seconds to make a guess on this problem, we would want to guess (B) or (C), since the other three have very extreme claims ("the most accurate / only cortisone / the best treatment usually"). Meanwhile, (B) and (C) have that lovable, easy-to-negate word "not". Those types of answers are "DEFENDER" answers: they are assuming that a certain objection to the argument is NOT true. They shield the argument from a potential objection. Like most causal arguments, this one wanted us to consider other possible ways to interpret some piece of evidence (in this case, why the cortisone caused pain relief).

#officialexplanation

[ChukwuemekaO466]

Many thanks for the explanation. However, I am still confused around how to eliminate "B". You mention that "Like most causal arguments, this one wanted us to consider other possible ways to interpret some piece of evidence (in this case, why the cortisone caused pain relief)."

And that's exactly what "B" does - it provides another possible way through which the cortisone caused pain relief, which is by "reducing the pressure on the inflamed nerve in the patient's leg"