Chemical pregnancy tests that measure the presence of human chorionic

Question

Chemical pregnancy tests that measure the presence of human chorionic gonadtropin (HCG) sometimes exhibit a false negative, indicating that the woman is not pregnant when in fact she is; the tests can also give a false positive response, indicating that the woman is pregnant when she actually is not. Consumers should seek the pregnancy test with the lowest proportion of false negative results in order to most accurately detect pregnancy with an at-home test.

The conclusion to the left is most strongly supported by which of the following, if true?

a) Some ultrasounds can detect pregnancy as early as one week into the gestation.
b) Early symptoms of a pregnancy can include nausea, increased hunger, and disturbed sleep patterns.
c) Prenatal medical supervision should begin as soon after conception as possible.
d) All at-home pregnancy tests have the same rate of inconclusive test results.
e) All at-home pregnancy tests produce the same proportion of false positive results.

KarishmaB · Accepted Answer

(E) is definitely the right answer here. Forget the process of elimination for a while. Think what the argument is telling you:

Premises: Pregnancy tests sometimes exhibit a false negative. The tests can also give a false positive.
Conclusion: Seek the test with the lowest proportion of false negative results in order to most accurately detect pregnancy with an at-home test.

So even before I look at the options, my issue is that 'most accurate detection' should include fewest 'false negatives' AND ALSO fewest 'false positives'.

The conclusion states that you need to look for lowest proportion of 'false negative' to accurately detect pregnancy. It doesn't say anything about 'false positive' which is not good. What would make the conclusion better i.e. strengthen it?
If I am told that all tests produce the same proportion of 'false positives', then it makes sense that I only need to worry about the 'false negative' proportion. It certainly makes the conclusion stronger.

Hence (E)

omerrauf · Answer

Answer should be E. Here is how.

There is a leap in the argument. You just need to identify the leap. Argument says pregnancy tests have false negtives and false positives. However, people should choose the pregnancy test with the lowest proportion of false negative results. The two statements need to be connected somehow for the conclusion to be correct. Conclusion is that people should choose the ones with the lowest proportion on False "Negative results". Which basically implies that there is more of a reason to chose these ones. That additional reason is only provided by E. If the false possitive ones rate is the same for all products, the only other thing that could help you make a choice is the difference in the "False Negative" ones.

Hence E

goalset · Answer

If all at-home pregnancy tests produce the same proportion of false positive results,then only one criteria is left to select the best test and it is the one which gives the lowest proportion of false negative results,hence E strengthens the conclusion.

metallicafan · Answer

First, you have to identify what is the scope of the question. What is the stimulus talking about?
It is talking about the chemical pregnancy tests, so if there are options that talk about other topics. They are wrong. That's the case of choices A, B, and C.

In the case of D, the stimuls doesn't talk about inconclusive test results.

E is the answer.

I suggest to read the CR Bible of Powerscore. It's a great book.

BukrsGmat · Answer

Process of elimination works here. But no way I can conclude the E the correct ans. :arh

. Experts please help. I did not get a satisfactory ans. I also faced the same question from Grockit. Any one knows any similar OG question

Jarvis07 · Answer

There are two problems with the tests:   1) False Positive  , and   2) False negative

Ideally, in order to avoid any false detection, we need to avoid both. However, the conclusion only talks about false negatives! But what about false positives?

The only reason for not talking about false positives could be that we can't do anything about them.  Therefore, it is simply not possible to pick low false positives.

Option E only talks about this. If all tests produce the same result, how on earth can we choose a test with less of false positives?

E it is.

VerbalBot · Answer

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Chemical pregnancy tests that measure the presence of human chorionic

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Chemical pregnancy tests that measure the presence of human chorionic

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