Logical reasoning PrepTest 110 · Section 3 · Question 19

Incorrect. The stimulus doesn't connect the retina's temperature to light being absorbed, so this answer is unsupported.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
Photons cause rhodopsin to change shape, which causes vision
Rhodopsin sometimes randomly changes shape, causing errors in vision
The hotter the retina, the more random shape changes there are

Answer Anticipation:
We can rely on two common logical features in this stimulus to anticipate an answer. First, we can focus on the causal statements; second, we can focus on statements that overlap.

The overlap between statements is in the second and third statement both discussing random shape changes. We know that increased temperature makes these random shape changes more frequent, and the shape changes cause visual errors. Putting those together, we can say that increasing the temperature of the retina will increase the frequency/amount of visual errors the creature experiences. Let's find an answer matching up with that.

Answer Explanation:
This answer talks about different temperatures, so the relationship from the third statement applies. Since the retina is a part of the body, it's temperature will vary with body temperature. And we know that, as body temperature increases, and retina temperature increases, rhodopsin will more frequently change shape, which will make visual errors more frequent. Therefore, these animals will have more error—prone visual systems when they're hot than when they're cold. This answer is supported by the stimulus, so it's the correct answer.

Key Takeaway:
The correct answer here is a great example of how the LSAT can take something that seems out of scope and bring it back into scope. By establishing a general relationship (the last statement), the correct answer could bring up a specific implementation of it. In this way, it can bring up something that's not directly mentioned in the stimulus while still being in scope.

Incorrect. There's no discussion of the speed with which rhodopsin reacts, so this answer is out of scope.

Incorrect. Surface area isn't discussed in the stimulus, so this answer is out of scope.

Incorrect. This answer is too strong. While rhodopsin is the only pigment discussed in the stimulus, it's never stated that there are no other pigments.