LSAT 155 | Section 1 | Logical Reasoning: Q6

LR Question 6 Explanation

QUESTION TEXT: In a counterattack on the harmful effects of acid rain…

QUESTION TYPE: Must be True

FACTS:

1. Wildlife experts are “liming” lakes.
2. This neutralizes acid and helps some acidified lakes.
3. Recurring treatment is necessary in some lakes because the water with the lime is replaced.
4. Lakes whose water is replaced more often than once per six months are not candidates for liming due to cost.

ANALYSIS: The first thing to keep in mind is from the question stem: remember that we want the answer that might not be true.

With that in mind, it’s probably easiest to look at the answer choices first on this question. Trying to rephrase something that is not true is not helpful, as there are many things that can’t be inferred here.

___________

1. This must be true. This is the contrapositive of fact 4, above. If lakes whose water is replaced more often than every 6 months are not candidates, then all candidates must not have water that is replaced more often than every 6 months.
2. This must be true. It’s basically the same as fact 3, above.
3. CORRECT. We don’t know that replacing reduces the impacts of acid rain. We only know that it reduces the effects of liming.
4. We know this is true from fact 2, above, which tells us that liming can help some lakes where acidification has harmed life.
5. This one must be true. Fact 4, above, tells us that cost prevents liming in lakes whose water is replaced frequently.

Recap: The question begins with “In a counterattack on the harmful effects of acid rain”. It is a Must be True question. Learn more about LSAT MBT questions in our guide to LSAT Logical Reasoning question types.