PrepTest 103

Incorrect. Why the countries have varying fat intake doesn't affect what impact that diet has on cancer rates.

Incorrect. This is a tempting answer, in that it sounds like it's raising an alternative cause—wealth. However, there's no inherent relationship between wealth and cancer rates. It's just as possible that something about a wealthy lifestyle increases cancer rates as that there's something about it that decreases cancer rates. Since wealth isn't inherently tied to cancer rates, this answer is out of scope.

Incorrect. This answer is trying to get you to fall for a common trap when presenting an answer that seems to be providing a counterexample. However, the stimulus talks about the relative incidence of cancer, not the absolute incidence. As such, low-fat countries could still have a prominent cancer rate, even if it's lower than an even more prominent cancer rate in high-fat countries.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
Fat intake and cancer rates are correlated, so anyone who wants to lower cancer risk should eat less fat.

Answer Anticipation:
The argument here establishes a very specific correlation between fat intake and cancer rates—it's a directly proportional relationship. That said, it's still a correlation, and this is a Weaken question, so we should start by looking at a Correlation/Causation flaw.

Taking a look at the conclusion, it's not explicitly causal, but it does imply a causal relationship. When it says that those who want to "reduce" risk "should reduce" their fat intake, it's putting forward the idea that lowering fat intake lowers cancer risk, which is a causal conclusion.

Since the argument jumps from a correlation to causation, the argument does feature a Correlation/Causation flaw, and we can weaken it using the standard methods:

(1) Identify an alternative cause
(2) Find counterexamples (cause without effect; effect without cause—but this argument talks about rates, and so this answer is very unlikely as the argument doesn't claim that everyone who eats a lot of fat will get cancer)
(3) Reverse causality (though it doesn't make sense to say that a high cancer risk leads the people for a country to eat more fat, so this is also an unlikely answer)

The most likely answer, then, is one that brings up an alternative cause of the cancer risk, so let's be on the lookout for that.

Answer Explanation:
Unlike answer choice (B), this answer does present an alternative cause that is inherently related to the supposed effect. Pollution, by definition, has an adverse health impact on humans, and so it's a viable alternative cause here, and thus it weakens the argument.

Key Takeaway:
Proportional relationships are correlations, and so any argument featuring them should be considered for a Correlation/Causation flaw.

Incorrect. When talking about population-wide stats, a few outliers as we see here won't affect the stats at all, making this answer too weak.