Logical reasoning PrepTest 131 · Section 2 · Question 11

Incorrect. This answer makes the paradox worse—if those on the Beta Diet also have other healthful habits, their lower average level of health is even more confusing.

Correct. Argument or Facts:
Facts

Question Type:
Paradox

Stimulus Summary:
The Beta Diet is healthier than a normal diet, but those who have been on it for decades are less healthy than those who aren't.

Answer Anticipation:
As in many Paradox questions, this stimulus compares several things. It starts by comparing the Beta Diet to a normal diet, and it states that the Beta Diet is healthier than a conventional diet. It then jumps to comparing those who have been on the Beta Diet for decades, stating that they're more likely to be in poor health than those with a normal diet. Why is the healthier diet correlated with worse health?

Since the argument jumped from comparing diets to comparing those on the diet, we need to find something different about this group that can explain why those on a healthier diet are having more health issues. And since it's based on a correlation between the diet and health issues, we can think about it in causal terms—what could cause these health issues? Well, if the person has a disease that causes them to eat a specific diet—think someone with heart disease, or diabetes—then they could be eating healthier while still having poorer health. Let's find this answer, or something that serves a similar role, explaining a relevant difference between those on the Beta Diet and those on a normal diet that would explain health issues in the former group.

Answer Explanation:
This answer choice matches our anticipation, providing a relevant difference between those on the Beta Diet and those on a normal diet that explains both why they're on the diet and why they have lower levels of health. If the Beta Diet is a treatment for a disease, then people on the diet would be expected to have health issues, regardless of how healthy the diet is.

Key Takeaway:
Paradox questions frequently rely on comparisons, but many of them also create the paradox by leaning on causal flaws. Here, the paradox stemmed from the assumption that a healthy diet would cause people to be healthy. The opposite correlation was found, however, and, much as in other question types that have correlation/causation issues, the correct answer ended up featuring an alternative cause of both being on the diet and being less healthy.

Incorrect. If the Beta Diet is resulting in better health for those who switch to it, then why isn't it working for those on it for several decades? And even if the healthful effects of the diet don't persist, that would at best explain why those on the Beta Diet for decades wouldn't have higher levels of overall health—it wouldn't explain why those on it have lower levels.

Incorrect. Be careful here—even though the Beta Diet has a bigger effect on some people than others, everyone in this answer is seeing some benefit from the Beta Diet. That makes the paradox of why those on the Beta Diet for decades are in worse health even worse.

Incorrect. There being a healthier diet out there doesn't change the fact that the Beta Diet is still healthier than a more conventional diet. And the stimulus compares those on the Beta Diet to those on a normal diet, so someone on this even more healthful diet doesn't factor into that comparison.