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Bunuel
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The city performed its annual testing of lead levels in the drinking 06 Sep 2021, 08:30
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35% (medium)

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71% (01:38) correct 29% (01:55) wrong based on 481 sessions

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The city performed its annual testing of lead levels in the drinking water and discovered that about 14 percent of the samples taken exceeded federal standards for allowable lead levels. Regardless of these findings, the lead levels, even in the ones that exceeded federal standards, were still too low to pose any immediate health threat. So, it’s perfectly safe for the city’s residents to drink all the tap water they want.

Which one of the following is an assumption on which the argument depends?


(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.

(B) The most dangerous contaminant in drinking water is lead.

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them.

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health.

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate.
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D
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The city performed its annual testing of lead levels in the drinking 09 Sep 2021, 04:32
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(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.
WRONG. Doesn't matter what the residents normally do, the argument talk about why the water is safe to drink

(B) The most dangerous contaminant in drinking water is lead.

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them.
WRONG. Statistics don't have to be most accurate since lead levels are anyway higher than the allowed levels

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health.
Tempting choice but WRONG according to me. The argument talks about short term effects. This talks about long term

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate.
WRONG. Not relevant to the argument

Premise:
14% of samples have lead levels above allowed standards
Lead is still low in levels to cause any immediate threat
Conclusion: City residents can drink this water all they want

My final choices were down to B and D. Since this is an assumption question, we are looking for a choice without which the argument falls apart. My answer is B since if there was something more dangerous than lead in the water, then the conclusion that people can drink as much as they want would not hold true (even in the short term).

VeritasKarishma nightblade354 please correct me if i'm wrong
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The city performed its annual testing of lead levels in the drinking 09 Sep 2021, 21:58
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roVanG
(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.
WRONG. Doesn't matter what the residents normally do, the argument talk about why the water is safe to drink

(B) The most dangerous contaminant in drinking water is lead.

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them.
WRONG. Statistics don't have to be most accurate since lead levels are anyway higher than the allowed levels

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health.
Tempting choice but WRONG according to me. The argument talks about short term effects. This talks about long term

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate.
WRONG. Not relevant to the argument

Premise:
14% of samples have lead levels above allowed standards
Lead is still low in levels to cause any immediate threat
Conclusion: City residents can drink this water all they want

My final choices were down to B and D. Since this is an assumption question, we are looking for a choice without which the argument falls apart. My answer is B since if there was something more dangerous than lead in the water, then the conclusion that people can drink as much as they want would not hold true (even in the short term).

VeritasKarishma nightblade354 please correct me if i'm wrong
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Option (B) is not correct.
(B) The most dangerous contaminant in drinking water is lead.
We do not need to assume that lead is the most dangerous contaminant. Perhaps arsenic is far more dangerous but our water has no arsenic or it has such a low concentration that it is harmless, we don't know.
If we negate the option, we get:
Lead is not the most dangerous contaminant in drinking water.
Does that impact our argument? No.

Yes, our conclusion is: the water is safe to drink.
There is an assumption that it has no other contaminant in a harmful concentration. But do we need to assume that lead is the most dangerous? No.

Now review the argument and options again.
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The city performed its annual testing of lead levels in the drinking 09 Sep 2021, 22:37
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Conclusion: it’s perfectly safe for the city’s residents to drink all the tap water they want.
Premise : the lead levels, even in the ones that exceeded federal standards, were still too low to pose any immediate health threat

There is a gap btwn the conclusion and premise. Immediate threat does not mean the water is safe.

(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.--Irrelevant or not necessary

(B) The most dangerous contaminant in drinking water is lead.-- Irrelevant

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them. -- Incorrect, this is not necessary to conclude

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health. -- Correct

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate. --Irrelevant
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The city performed its annual testing of lead levels in the drinking 11 Sep 2021, 07:30
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Bunuel
The city performed its annual testing of lead levels in the drinking water and discovered that about 14 percent of the samples taken exceeded federal standards for allowable lead levels. Regardless of these findings, the lead levels, even in the ones that exceeded federal standards, were still too low to pose any immediate health threat. So, it’s perfectly safe for the city’s residents to drink all the tap water they want.

Which one of the following is an assumption on which the argument depends?


(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.

(B) The most dangerous contaminant in drinking water is lead.

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them.

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health.

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate.
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OFFICIAL EXPLANATION



Answer: D

STEP 1: Read the question and identify your task.
This is an Assumption question. For this first question you must find the assumption that the argument depends on in order to hold true.

STEP 2: Read the argument with your task in mind.
The argument is about annual tests of the lead levels in drinking water. The conclusion is that the water is safe to drink, even though some samples
exceeded federal standards, because the levels were still too low to pose any risks.

STEP 3: Know what you’re looking for.
The correct answer will address the relationship between the federal standards and the amount of lead that causes health problems.

STEP 4: Read every word of every answer choice.
Answer A says the standards are too stringent, but the lead levels still may be harmful to people’s health, and whether they disregard the guidelines or not, they take a risk by drinking the water. Answer B seems to weaken rather than support the argument, and that is not what the question is asking. Answer C calls into question the method of testing and leaves open the option that the situation might be worse than stated, possibly leading to the opposite recommendation, that people should not drink the water. For answer D, if lead levels slightly above federal standards are still not harmful to people’s health, then it is valid to say that drinking the water is still safe for the city’s residents. This very much supports the argument and is critical for the argument’s conclusion. Answer E has nothing to do with the lead levels or drinking the water. Rather, it gives an irrelevant observation about human behavior. Therefore, answer D is the correct choice.
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The city performed its annual testing of lead levels in the drinking 22 Sep 2024, 22:09
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The argument says were still too low to pose any immediate health threat, but in option D we are talking about long term health threat. Is there any relevance of this ???
Bunuel
Bunuel
The city performed its annual testing of lead levels in the drinking water and discovered that about 14 percent of the samples taken exceeded federal standards for allowable lead levels. Regardless of these findings, the lead levels, even in the ones that exceeded federal standards, were still too low to pose any immediate health threat. So, it’s perfectly safe for the city’s residents to drink all the tap water they want.

Which one of the following is an assumption on which the argument depends?


(A) The city’s residents often disregard federal guidelines when it comes to public health issues because the standards are overly stringent.

(B) The most dangerous contaminant in drinking water is lead.

(C) Statistical sampling is not the most accurate basis for determining health threats even though the federal government and the city must depend on them.

(D) Lead levels even slightly above federal standards do not have long-term effects on people’s health.

(E) People feel safer when they heed warnings from the federal government even if they are not entirely accurate.



OFFICIAL EXPLANATION



Answer: D

STEP 1: Read the question and identify your task.
This is an Assumption question. For this first question you must find the assumption that the argument depends on in order to hold true.

STEP 2: Read the argument with your task in mind.
The argument is about annual tests of the lead levels in drinking water. The conclusion is that the water is safe to drink, even though some samples
exceeded federal standards, because the levels were still too low to pose any risks.

STEP 3: Know what you’re looking for.
The correct answer will address the relationship between the federal standards and the amount of lead that causes health problems.

STEP 4: Read every word of every answer choice.
Answer A says the standards are too stringent, but the lead levels still may be harmful to people’s health, and whether they disregard the guidelines or not, they take a risk by drinking the water. Answer B seems to weaken rather than support the argument, and that is not what the question is asking. Answer C calls into question the method of testing and leaves open the option that the situation might be worse than stated, possibly leading to the opposite recommendation, that people should not drink the water. For answer D, if lead levels slightly above federal standards are still not harmful to people’s health, then it is valid to say that drinking the water is still safe for the city’s residents. This very much supports the argument and is critical for the argument’s conclusion. Answer E has nothing to do with the lead levels or drinking the water. Rather, it gives an irrelevant observation about human behavior. Therefore, answer D is the correct choice.
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