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#23499
Complete Question Explanation

Parallel Reasoning-SN. The correct answer choice is (B)

This is a Parallel Reasoning question and, as was probably evident from the length of the answer choices, a time-consuming one. The stimulus is stating that you can not conclude that a person has this infection simply based upon the presence of bacteria. The individual must also be physically run down for infection to occur. This Parallel Reasoning question is probably best attacked using the Test of Abstraction. Basically, what the stimulus is stating is that you cannot make a determination based on the existence of just one factor; the second factor must be present as well.

Answer Choice (A): While this answer is a little bit tricky, it is not dealing with the same analysis because it uses causal reasoning. Here, the existence of two different factors could be the exclusive cause of blurred vision. In the stimulus, it is necessary that two different factors exist before we can determine that infection has occurred.

Answer Choice (B): This is the correct answer choice. Here, you cannot make a determination of the health of the plant merely based upon a singular factor — the plant receiving six hours of light. Another factor must also be in existence — slightly alkaline soil.

Answer Choice (C): While this answer choice is somewhat similar in that you cannot make a determination based upon a singular factor, it is no secondary factor that must exist in order to make the determination.

Answer Choice (D): Applying the Test of Abstraction here would garner a statement along the lines of "two is not necessarily better than one." This is not the same reasoning used in the stimulus.

Answer Choice (E): Applying the Test of Abstraction her would garner a statement along the lines of "a one time occurrence is insufficient, there must be chronic occurrences in order to make a determination." Again, this is not the same reasoning used in the stimulus.
 yrivers
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#35702
Hi,

I'm finishing the HW from class lecture and can't find which exam this question belong to. But would much appreciate help with it.

It'd be wrong to conclude that a person has Streptococcus infection if there is no other evidence that the fact that Streptococcus bacilli are present in the person's throat; after all, infection does not occur unless the host is physically run down.

Could you please diagram and help me understand how to understand the stimulus and eliminate/select the correct answer?

For the stimulus, I had:
NOETT --> WCSI
I --> RD

Thank you!
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 Jonathan Evans
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#35775
Hi, YRivers,

Good question! I have moved this question to its test section (PrepTest 22, June 1997).

The structure of the stimulus is as follows:
  • Conclusion: It is not true that (SB :arrow: Inf).
    Premise: Inf :arrow: Run Down
In other words, the author concludes that the presence of Strep bacteria is not by itself sufficient to imply infection, because infection requires that a person be run down.

Thus, we need an answer in which we conclude that one condition is not by itself sufficient for a second because the latter requires a third condition:
  • Conclusion: Not true that (A :arrow: B)
    Premise: B :arrow: C
This matches up with answer choice (B). Sun is not sufficient for blooming because blooming also requires alkaline soil.

I hope this helps!
 mN2mmvf
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#41034
Hi! I understood where this stimulus was going -- that there were two necessary conditions to being declared as having strep, and only one was present. That's true for answer (B). But why isn't it also true for (E)? In that choice, in order for a patient to have hypertension, they must have 1) a high blood pressure reading, and 2) a chronic history of such readings. It seemed right to me to argue that "a person cannot be presumed to be hypertensive on the basis on a high reading" alone for exactly that same reasoning.
 Claire Horan
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#42204
Hi mN2mmvf,

Good observation! You will often find that more than one answer choice seems parallel. That's why it is important to keep refining your prephrase until you end up with the contender that is the most parallel.

You correctly state that the stimulus lists two requirements for diagnosing strep: 1) the presence of the bacteria and 2) the host is physically run down. Note that these two requirements are independent of one another. The two requirements in (B) are also independent of each other: 1) sunlight and 2) alkaline soil.

In answer choice (E), the problem is only superficially that there are two requirements and only one has been met. Instead, there is actually only one requirement for hypertension, that a person have chronically high blood pressure. The problem is more that a proper diagnosis cannot depend upon outlier data points. In other words, hypertension cannot be diagnosed based on an unrepresentative reading.

One last reason to be suspicious of (E) is that it's a shell game: both the stimulus and answer choice (E) involve medical diagnoses.
 Blueballoon5%
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#47904
Jonathan Evans wrote:Hi, YRivers,

Good question! I have moved this question to its test section (PrepTest 22, June 1997).

The structure of the stimulus is as follows:
  • Conclusion: It is not true that (SB :arrow: Inf).
    Premise: Inf :arrow: Run Down
In other words, the author concludes that the presence of Strep bacteria is not by itself sufficient to imply infection, because infection requires that a person be run down.

Thus, we need an answer in which we conclude that one condition is not by itself sufficient for a second because the latter requires a third condition:
  • Conclusion: Not true that (A :arrow: B)
    Premise: B :arrow: C
This matches up with answer choice (B). Sun is not sufficient for blooming because blooming also requires alkaline soil.

I hope this helps!
Hello! I was curious, what is the difference between these two: (for diagraming purposes)

1.) It is not true that (SB :arrow: Inf).
2.) NOT SB :arrow: NOT Inf
 James Finch
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#62627
Hi Blue Balloon,

What "It is not true that (SB :arrow: Inf)" means is that the conditional of SB :arrow: Inf is not actually true, meaning that there isn't actually a conditional relationship at all between SB presence and an infection. This is very different from SB:arrow: Inf, which is stating that there is a relationship between the two, namely that not having SB present means that there is no infection, and thus if there is an infection there must be SB present.

Hope this clears things up!
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 hifigirl
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#105769
Hi!

In order to arrive at the correct answer choice (B), you have to recognize that the final sentence is the position advocated for. The directors SHOULD OBTAIN permission from those who made the donations.

(A) is eliminated because the directors are being heavily restricted if they cannot allocate publicly solicited funds to any purposes for which the directors had not earmarked the funds in advance. It discredits most of the stimulus, arguing for the directors to donate the surplus of funds. Most importantly, the position advocated for "obtaining permission" is disregarded.
(C) is eliminated because it disregards the position advocated for by suggesting a "return of all the money" rather than appealing to the donors, and heavily restricts the directors to only spend the funds on the relevant cause.
(D) is eliminated because it directly contradicts the position of directors obtaining permission from donors by saying the donors cannot delegate to the directors at all.
(E) is eliminated because it directly contradicts that the directors should obtain permission from those who made the donations, instead advocating for full trust in the directors for "whatever circumstance might arise." Although (E) places least restriction on the directors, it does not adhere to the position advocated for.
(B) is the correct answer choice because it contains keywords "wishes of the donors," although disposing of the funds is wild behavior, it completely adheres to the position advocated for.

It is not the least restrictive but compared to the other answer choices and through process of elimination, (B) is the best answer choice.
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 hifigirl
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#105771
Hi!

The stimulus follows that additional evidence other than presence of Streptococcus bacilli in the person's throat is needed to conclude that the person has the infection. For example, the infection doesn't occur unless the person has a weakened immune system.

(A) discusses an additional cause of blurred vision (certain drugs). Careful here because the stimulus is talking about evidence for an infection, not additional causes of the infection.
(B) is the correct answer choice because it points at the additional necessary condition for the healthy lavender plant to bloom. It mirrors the stimulus because in addition to direct sunlight, slightly alkaline soil is needed to bloom. In addition to presence of Strep in the throat, a physically run down host is needed to conclude Strep infection
(C) mentions a "very good defense mechanism" which dispels the initial low temperature cause... it would be closer if it mentioned another reason bee colonies fail to survive the winter, but even then it would be a closer mirror of AC (A) which is cause-focused. The survival of the colony vs. individual bees is irrelevant as the stimulus is not focused on a group of people vs. one person with the infection.
(D) is stating two is not better than one for the plant to produce berries, which is irrelevant and contradictory to the stimulus where two pieces of evidence are better than one... this is just a bad answer choice and does not resemble the stimulus whatsoever.
(E) is wrong because it is not arguing for an additional piece of evidence for a hypertensive diagnosis. Instead, it argues that the evidence necessary to be hypertensive = people who already have chronically high blood pressure. This is the same element and exhibits a circular reasoning, not a different piece of evidence.

Hope that helps!

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