Logical reasoning PrepTest 122 · Section 4 · Question 8

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
Pollen from plants unique to an area can link a relic to an area, so analyzing that pollen can give clues as to where that relic has been.

Answer Anticipation:
This argument falls into a common pattern seen on the LSAT—one where a certain piece of information is used as a proxy to determine another piece of information. Here, pollen is being used to determine location, via the plants unique to a region. So, in reality, pollen is being used as a proxy for the plants, and plants are being used as a proxy for the location of the relic!

Whenever one thing is being used as a proxy to determine another, you should start to consider how good of a proxy it is. In other words, is there another explanation for how that proxy ended up being present.

Here, is there another way for the pollen to be present on the relic other than it being in the region where the unique plants exist? We know the plants are unique to certain areas, but that doesn't mean the pollen is. Presumably, pollen can travel (on the wind, on insects), and so any answer suggesting that the pollen could have ended up on the relics while they weren't in the regions of the plants the pollen came from will weaken this explanation.

Answer Explanation:
This answer suggests that the pollen may have ended up on the relics while they weren't located in the regions with the unique plants. This calls into question the method of using pollen to determine location, thus weakening the argument.

Key Takeaway:
Whenever one measurement or metric is used as a proxy for another, there's always the chance that that proxy is imperfect (or even irrelevant). Look for answers addressing any disconnect between the proxy and what metric/measurement is showing up in the conclusion.

Incorrect. Less complicated methods existing doesn't invalidate the use of a more complicated method. As such, this answer is out of scope.

Incorrect. The method described in the stimulus uses pollen from plants that are unique to specific regions, so pollen that's common in multiple regions wouldn't be used in this method, and thus this answer is out of scope.

Incorrect. The stimulus talks about plants that are "known" to have been unique to certain areas, so the pollens and plants discussed in this answer aren't the ones used by the method, making this answer out of scope.

Incorrect. Painstaking and expensive don't tell us whether the method is accurate, and that's what matters to the argument.