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- Tue Sep 21, 2021 4:05 pm
#90636
Complete Question Explanation
Must Be True, Except. The correct answer choice is (C).
In this stimulus, we are taught a method for helping manage the acidification of lakes. It tells us that experts have begun adding lime to these lakes to balance out the acidification. The stimulus is not very strongly worded. The process helps "some" acidified lakes and staves off "some" potential damage caused by acid rain. In a Must Be True, Except question, we like this broad language. It should make it easier to find answer choices we can prove by the facts in the stimulus.
The second half of the stimulus uses stronger language. In the second part, the stimulus explains that a lake that has been treated with lime needs to be periodically treated again because the lime water is carried away from time to time as a part of the water cycle. However, there's a limit to how often you can treat a lake with lime. It becomes cost inefficient if it needs to be retreated every six months (or less).
This is a Must Be True type question, so we aren't surprised that the stimulus doesn't provide an argument. It is a set of facts that we can link together to determine a number of things about the process and value of adding lime to lakes. For a Must Be True, Except question, we are looking for four answer choices we can prove with the stimulus and one answer choice that is not proven by the stimulus. Typically, the correct answer here will be one that we lack sufficient information about if it's true or not. However, it could also be an answer choice that is inconsistent with the facts in the stimulus.
Answer choice (A): This answer choice is easily proven by the second part of the stimulus. It tells us that if a lake requires liming every six months or sooner, then it is not a candidate for liming. So if a lake is a candidate for liming, it must only need liming every six months or less often than that. Since we can prove this answer choice based on the stimulus, we can eliminate it.
Answer choice (B): We know from the stimulus that liming does not work forever. Gradually, the water with lime is taken out of the lake and thus the lake will need more lime added.
Answer choice (C): This is the correct answer choice. This answer choice is exactly what we are looking for. It starts off with the words "unlimed lakes...." which is immediately suspicious here. We know very little about unlimed lakes. Our stimulus is all about lakes where lime has been added. This answer choice dives into a situation that we just can't prove one way or the other. I might have a guess about if lakes with frequently replaced water are less likely to be harmed by acid rain, but I can't point to anything in the stimulus to prove my instincts.
Answer choice (D): The stimulus here tells us that wildlife experts use lime in lakes where the animals have already been harmed by acid rain. It can restore the health of some lakes where acid rain has already caused damage. Those facts from the stimulus support this answer choice.
Answer choice (E): This answer choice is supported by the final sentence of the stimulus. It gives us the time frame that frequent liming becomes cost ineffective---six months. This supports the idea that frequent liming would make the process not cost-effective.
Must Be True, Except. The correct answer choice is (C).
In this stimulus, we are taught a method for helping manage the acidification of lakes. It tells us that experts have begun adding lime to these lakes to balance out the acidification. The stimulus is not very strongly worded. The process helps "some" acidified lakes and staves off "some" potential damage caused by acid rain. In a Must Be True, Except question, we like this broad language. It should make it easier to find answer choices we can prove by the facts in the stimulus.
The second half of the stimulus uses stronger language. In the second part, the stimulus explains that a lake that has been treated with lime needs to be periodically treated again because the lime water is carried away from time to time as a part of the water cycle. However, there's a limit to how often you can treat a lake with lime. It becomes cost inefficient if it needs to be retreated every six months (or less).
This is a Must Be True type question, so we aren't surprised that the stimulus doesn't provide an argument. It is a set of facts that we can link together to determine a number of things about the process and value of adding lime to lakes. For a Must Be True, Except question, we are looking for four answer choices we can prove with the stimulus and one answer choice that is not proven by the stimulus. Typically, the correct answer here will be one that we lack sufficient information about if it's true or not. However, it could also be an answer choice that is inconsistent with the facts in the stimulus.
Answer choice (A): This answer choice is easily proven by the second part of the stimulus. It tells us that if a lake requires liming every six months or sooner, then it is not a candidate for liming. So if a lake is a candidate for liming, it must only need liming every six months or less often than that. Since we can prove this answer choice based on the stimulus, we can eliminate it.
Answer choice (B): We know from the stimulus that liming does not work forever. Gradually, the water with lime is taken out of the lake and thus the lake will need more lime added.
Answer choice (C): This is the correct answer choice. This answer choice is exactly what we are looking for. It starts off with the words "unlimed lakes...." which is immediately suspicious here. We know very little about unlimed lakes. Our stimulus is all about lakes where lime has been added. This answer choice dives into a situation that we just can't prove one way or the other. I might have a guess about if lakes with frequently replaced water are less likely to be harmed by acid rain, but I can't point to anything in the stimulus to prove my instincts.
Answer choice (D): The stimulus here tells us that wildlife experts use lime in lakes where the animals have already been harmed by acid rain. It can restore the health of some lakes where acid rain has already caused damage. Those facts from the stimulus support this answer choice.
Answer choice (E): This answer choice is supported by the final sentence of the stimulus. It gives us the time frame that frequent liming becomes cost ineffective---six months. This supports the idea that frequent liming would make the process not cost-effective.
