LSAT 157 – Section 3 – Question 15

LSAT 157 - Section 3 - Question 15

June 2020

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Question
QuickView		 Type Tags Answer
Choices		 Curve Question
Difficulty		 Psg/Game/S
Difficulty		 Explanation
PT157 S3 Q15
+LR
Weaken +Weak
A
4%
145
B
13%
146
C
83%
160
D
1%
142
E
0%
140
134
142
149
 +Medium 145.111 +SubsectionEasier

Ants sometimes live in hollow places in the roots of a certain orchid species. Those orchids of that species that house ants are far healthier than those that do not. Since the ants store organic matter in the orchids’ roots, an explanation for the superior health of the orchids that house ants is that the organic matter stored by the ants provides those orchids with additional nutrients.

Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that ants are more likely to live in healthy orchid species because the ants store organic matter, thereby providing the orchids with additional nutrients.

Notable Assumptions
The author assumes that the organic matter brought by the ants are *causing* the orchids to be healthier. It could be equally true that healthy orchids attract ants to store their nectar (or some other variable).
The author also assumes that the ants’ presence does not harm the orchid in other ways.

A
Microscopic organisms that are present in the orchids’ roots break down the organic matter stored there by the ants.
If anything, this strengthens the link between organisms, bolstering the health of orchids. Thus, this does not weaken the argument.
B
The nutrients present in the organic matter stored by the ants are the same as those present in the soil in which the orchids are found.
While this suggests that the ants may not provide *unique* nutrients, it does not explain why the orchids are healthier. You have to make some unwarranted assumptions for this to work.
C
The ants that live in hollow places in the roots of orchids prey on an insect species whose members eat the orchids’ roots.
While this may look unrelated, it provides another explanation for *why* orchids with ants are healthier. If the ants hunt a species prone to eating the orchid’s roots, it explains the orchid’s improved health.
D
The ants that live in hollow places in the roots of orchids do not play a role in pollinating the flowers of the plant.
It does not matter whether the ants pollinate the plant. This does not provide an alternative explanation or weaken the argument.
E
Most plant species whose roots, stems, or leaves harbor insects are more prone to disease and rot than are other plants.
This is not specific enough to be applied to the ants and orchids. Also, it does not address why the orchids are healthier.

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LSAT PrepTest 157 Explanations

Section 1 - Reading Comprehension

Section 2 - Logical Reasoning

Section 3 - Logical Reasoning

Section 4 - Reading Comprehension

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