LSAT 92 - Section 1 - Question 11

This is a Main Conclusion question.

The stimulus contains an argument with many complications. It starts with other people's argument. OPA is a causal argument moving from a correlational premise to a causal conclusion. The author responds to OPA by pointing out the possibility of an alternate cause. She does so by pointing out another correlation that wasn't considered by OPA. She concludes that OPA wasn't well reasoned.

First, we learned that North Americans are becoming more lethargic. In the third sentence, we find out that North Americans are also consuming more fast food meals. This is the correlational phenomenon which OPA—“one researcher”—uses to support his causal conclusion in the second sentence. OPA concludes that fast food has an adverse effect (casual) on people's health. Note the assumption that lethargy is bad for health.

The author begins her argument with “however.” The first thing she tells us is that few lethargic adults exercise regularly. This is introducing another correlation. OPA told us that lethargy is correlated with increased consumption of fast food. The author is telling us that lethargy is also correlated with less exercise. But more than that, the author says this correlation is actually causal because lack of exercise can contribute to lethargy.

Now we get to the author's conclusion, which is that OPA delivered a weak argument. The lethargy studies do not settle the question of whether fast food is unhealthy. In other words, the correlation between lethargy and fast food isn’t dispositive evidence that fast food causes lethargy and hence poor health. Why? Because an alternative explanation of the lethargy studies is available through its correlative and causal relationship with exercise.

Note that the last sentence of the stimulus is in fact the main conclusion and it has a conclusion indicator “thus” preceding it. This is a good reminder that shortcuts don't always work. In general, we’re better off focusing on the fundamentals rather than playing mind games with the test writers.

Answer Choice (A) is a premise of the author's argument.

Answer Choice (B) states something new and therefore cannot be the conclusion. It says that high consumption of fast food is a health risk only when combined with a lack of regular exercise. Given the information in the stimulus, I have no idea if that's true.

Answer Choice (C) says the researcher’s data show that the consumption of fast food is not the main cause of poor health in North Americans. This might be tempting, but this isn’t the main conclusion. There is a big difference between something not being the main cause versus not knowing whether something is the main cause. The author's conclusion is simply that whether fast food is unhealthy isn't settled by the lethargy studies. That's a much more modest claim than what's present in (C), which says that it is settled and we know definitively that fast food is not the main cause of poor health. That's not what the author was trying to say. The author pointed out exercise simply to reveal OPA's failure to consider alternative causes.

Answer Choice (D) says the lethargy studies failed to consider one probable cause of lethargy. This is not exactly right. The author criticizes OPA for failing to consider one probable cause of lethargy. Both the author and OPA use the lethargy studies as a starting point. Neither criticizes that study.

Correct Answer Choice (E) says the researcher's conclusion was not adequately justified by the lethargy studies. This is exactly right, and if you map the language from this answer onto the content of the argument, you get a correlation-causation flaw. The researcher's conclusion is that fast food causes lethargy. The lethargy studies are what supply half of the correlation between lethargy and fast food consumption. The author is simply saying that the correlation between lethargy and fast food doesn't adequately justify the conclusion that fast food causes lethargy.