LSAT 102 | Section 2 | Logical Reasoning: Q15

LR Question 15 Explanation

QUESTION TEXT: Some plants have extremely sensitive biological…

QUESTION TYPE: Weaken

CONCLUSION: You could tell a thermometer that read “1 degree Celsius” was accurate to within 1 degree if you saw both:

1. Rhododendrons with uncurled leaves, AND
2. A mature crocus whose blossoms weren’t open.

REASONING: If it were zero or colder, the rhododendron leaves would curl. If it were 2 degrees or higher, the crocus blossoms would open.

ANALYSIS: This sounds like a good argument. The right answer introduces a new consideration: rhododendrons are really tall, and it’s chilly up there.

So a thermometer on the ground could say 1 degree, and be correct, even the rhodendrons could be at -1, and curled.

___________

1. This sounds good, but we don’t care about rhododendron blossoms. We only know what their leaves do.
    
   It also doesn’t matter that crocuses only blossom a few weeks per year. The stimulus talks about mature but unopened blossoms, which will open if it gets warm enough. Presumably this method is only available during crocus blossom season.
2. This is one of the least relevant answers I’ve ever seen. We’re talking about how to judge whether a thermometer is accurate. This just tells us that people get cold at a certain temperature.
3. We don’t care about how the two plants grow. We care about how they react to temperature.
4. CORRECT. This does it: the plants aren’t experiencing the same temperature. They can’t serve to accurately judge a thermometer to 1 degree, since they themselves will be off by more than 2 degrees.
5. That’s fine. The whole point of the stimulus is that the two plants can tell us whether a thermometer is accurate.

Recap: The question begins with “Some plants have extremely sensitive biological”. It is a Weaken question. Learn how to master LSAT Weaken questions on the LSAT Logical Reasoning question types page.