Logical reasoning PrepTest 120 · Section 4 · Question 2

Incorrect. This answer establishes that temperature changes do affect the behavior of this type of butterfly, which strengthens the argument by connecting the cause and effect using causal language ("affected").

Incorrect. This answer strengthens the argument by explaining the causal relationship—the climate change causes certain plants to move north, and the butterflies move north with them.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Bizarro Strengthen

Stimulus Summary:
The checkerspot butterfly's northward shift correlated with climate change, so the climate change is causing the northward shift.

Answer Anticipation:
A premise that explicitly discusses one thing being "correlated" with another is almost certainly leading to a Correlation/Causation flaw, especially in a Strengthen question (where that flaw is the most common by far). When we get around to the conclusion and see that it talks about one thing being "responsible" for another, we can confirm the presence of that flaw.

So the good Doctor here treats a correlation between a warm temperature shift and a butterfly shift as proof that climate change is causing the butterflies to move north. As such, we can strengthen this argument using the normal methods:
(1) Eliminate an alternative cause
(2) Find more examples of the butterfly heading north (though this seems unlikely as a source of an answer since the stimulus already talks about the population as a whole)
(3) Find a control group (butterflies in areas that haven't seen a temperature shift and have stayed in place)
(4) Explanation of how the causality works

The last one is pretty rare in Strengthen questions, but it shows up more frequently in Bizarro Strengthen questions, so we should generally think about it here.

Answer Explanation:
If the checkerspot butterfly is very adaptable, there's no reason why it shouldn't have already been present up north, or why it couldn't have adapted to the weather down south. As such, this answer suggests that there's something else going on to cause the migration, weakening the argument. Something that weakens the argument is correct in a Bizarro Strengthen question.

Key Takeaway:
This Bizarro Strengthen question highlights two things you should be aware of in this question type. First, it's more likely that you see (incorrect) answers that strengthen the argument by explaining the causality. Second, you're more likely to get (incorrect) answers that barely strengthen the argument. For this question type, correct answers are generally out of scope or weakeners, not answers that are in the ballpark but too weak to actually strengthen it.

Incorrect. This answer establishes another correlation between temperatures and checkerspot butterfly populations, which strengthens an argument. Correlation doesn't prove causation, but it is evidence for it.

Incorrect. While not an answer that does all that much to strengthen the argument, this answer does show that closely related butterfly species are affected by temperature, providing some evidence that climate change could be affecting the checkerspot butterfly. This is a weaker version of answer choice (A), but we don't need answers that strengthen the argument substantially, just answers that strengthen the argument.