LSAT 3 | Section 4 | Logical Reasoning: Q10

LR Question 10 Explanation

QUESTION TEXT: Nature constantly adjusts the atmospheric carbon level…

QUESTION TYPE: Must be True – Exception

CONCLUSION: Environmentalists should relax about carbon emissions, nature will take care of them.

REASONING: Nature has regulated its own carbon level in the past.

ANALYSIS: This is not a good argument, since the author admits that sustained emissions would be harmful.

We do know some things though:

1. Carbon increase ➞ atmospheric heat increased ➞ evaporation from oceans ➞ more rain ➞ more carbon washed into ocean seabed
2. Carbon decrease➞ less atmospheric heat ➞ decreased evaporation from oceans ➞less rain ➞ less carbon washed into ocean seabed

You cannot hope to answer this type of question unless you map out the possibilities, either mentally or on paper. If I were just drawing for myself, I would use 1-2 letter symbols, such as C ➞ H ➞ E ➞ R ➞ O. (Carbon, Heat, Evaporation, Rain, Ocean).

___________

1. Look at number 2. Less heat causes less carbon washed into the seabed.
2. Look at number 1. Going left to right, we see that more carbon does lead to more evaporation.
3. Number 1 tells us this is true.
4. Number 2 tells us this is true.
5. CORRECT. This is false. It is an increase in atmospheric heat that causes a decrease of carbon. More heat leads to more rain, which leads to more carbon being washed into the seabed.

Recap: The question begins with “Nature constantly adjusts the atmospheric carbon level”. It is a Must be True question. Learn more about LSAT MBT questions in our guide to LSAT Logical Reasoning question types.