Logical reasoning PrepTest 143 · Section 1 · Question 11

Incorrect. This answer doesn't affect the argument since it's about a drop in the crime rate. Even if the police chief's city has a higher crime rate than in other areas, that rate could have dropped precipitously during the chief's tenure.

Incorrect. As long as the crime rate dropped during the police chief's tenure, it doesn't matter what it is compared to decades earlier.

Incorrect. This answer aligns with the chief's strategy being effective, as it was used during a time when crime fell and then stayed down.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
PC: Crime has dropped 20% while I've been chief, so my strategy must be the cause.

Answer Anticipation:
Weaken questions frequently feature correlation/causation flaws, so you should always be on the lookout for correlative premises and causal conclusions when dealing with this question type.

Here, the very first word—"During"—can introduce a correlation, so you should have been on alert from the get-go. The conclusion here is also causal—"the result of"—and so we have a correlation/causation flaw in this argument.

When we're trying to weaken an argument with such a flaw, the correct answers generally:

(1) Identify an alternative cause
(2) Show counterexamples (the cause without the effect; the effect without the cause)
(3) Provide evidence of reverse causality (which wouldn't make sense here, so it's unlikely to be the correct answer)

Answer Explanation:
This answer suggests that the crime rate in the police chief's city has fallen less than the rest of the country—this suggests some other reason for a nation-wide drop in crime and that the police chief's city actually is worse than other places, thus providing evidence that the strategy might actually cause crime to be worse than without them.

Key Takeaway:
Actively look for correlation/causation flaws in Weaken questions—they show up quite frequently (nearly 50% of the time).

Incorrect. The argument discusses overall crime rates, so crime differentials within parts of the city are out of scope.