Chronic fatigue syndrome is characterized by prolonged fatigue, muscul

Question

Chronic fatigue syndrome is characterized by prolonged fatigue, muscular pain, and neurological problems. It is not known whether these symptoms are all caused by a single virus or whether each symptom is the result of a separate viral infection. A newly synthesized drug has been tested on those who suffer from chronic fatigue syndrome. Although the specific antiviral effects of this drug are unknown, it has lessened the severity of all of the symptoms of chronic fatigue syndrome. Thus there is evidence that chronic fatigue syndrome is, in fact, caused by one virus.

The argument assumes which one of following?

(A) All those who suffer from prolonged fatigue also suffer from neurological problems.

(B) It is more likely that the new drug counteracts one virus than that it counteracts several viruses.

(C) The symptoms of chronic fatigue syndrome are dissimilar to those of any other syndrome.

(D) Most syndromes that are characterized by related symptoms are each caused by a single viral infection.

(E) An antiviral medication that eliminates the most severe symptoms of chronic fatigue syndrome thereby cures chronic fatigue syndrome.

Abhishek009 · Answer

CF characterisced by : (1) prolonged fatigue (2) muscular pain, and (3) neurological problems. 
Info about symptoms ( 1 to 3 ) is caused by single virus/diff virus is not known.
The new drug has reduced all the symptoms - Hence the author concludes that chronic fatigue syndrome is, in fact, caused by one virus.

Try to negate option (B) the conclusion falls apart, hence correct Answer must be (B)

sayan640 · Answer

The conclusion is in the last sentence starting with conclusion marker "thus".
The conclusion is :- Chronic fatigue syndrome is ,in fact, caused by one virus.
Premise :- Newly synthesized drug has reduced all the symptoms of chronic fatigue syndrome.
Missing link :- It is more likely that the drug acts on only one virus.

Option B states that and hence is the correct answer.

Posted from my mobile device

warrior1991 · Answer

Read the below lines and you will reach to the conclusion.

One drug was tested on those who suffer from chronic fatigue syndrome. This drug lessened the severity of all of the symptoms of chronic fatigue syndrome.

From this the conclusion came out that chronic fatigue syndrome is caused by one virus.

We,now, can prethink that one drug that was given actually countered 3 problems of chronic fatigue syndrome in one or the other sense.

1. Either it acted on all 3 equally.
2. It acted on 1 and that 1 acted on other 2.

Option B highlights the 2nd point .

Therefore B is correct.

nandeta · Answer

Chronic fatigue syndrome is characterized by prolonged fatigue, muscular pain, and neurological problems. It is not known whether these symptoms are all caused by a single virus or whether each symptom is the result of a separate viral infection. A newly synthesized drug has been tested on those who suffer from chronic fatigue syndrome. Although the specific antiviral effects of this drug are unknown, it has lessened the severity of all of the symptoms of chronic fatigue syndrome. Thus there is evidence that chronic fatigue syndrome is, in fact, caused by one virus.

The argument assumes which one of following?

(A) All those who suffer from prolonged fatigue also suffer from neurological problems. 
Wrong. Conclusion states that chronic fatigue is caused by one virus. People from prolonged fatigue also suffer from neurological problems strengthen it, but does not provide assumption.

(B) It is more likely that the new drug counteracts one virus than that it counteracts several viruses.  
Right. Drug is showing positive results, and if drug is made to counteract for one virus only, then the disease is of course made of one virus only.

(C) The symptoms of chronic fatigue syndrome are dissimilar to those of any other syndrome. 
Wrong. How does it help the conclusion that chronic fatigue syndrome is made of one virus? It's symptoms can be similar to other syndromes which are made of multiple viruses.

(D) Most syndromes that are characterized by related symptoms are each caused by a single viral infection. 
Wrong. We cannot compare one disease with another on basis of its single viral infection. There are alot many factors involved.

(E) An antiviral medication that eliminates the most severe symptoms of chronic fatigue syndrome thereby cures chronic fatigue syndrome. 
Wrong. This is a conclusion and not an assumption.

KarishmaB · Answer

Premises: Chronic fatigue syndrome is characterized by prolonged fatigue, muscular pain, and neurological problems. It is not known whether these symptoms are all caused by a single virus or separate viruses. A newly synthesized drug has been tested on those who suffer from chronic fatigue syndrome. The specific antiviral effects of this drug are unknown, but it has lessened the severity of all of the symptoms of chronic fatigue syndrome. Conclusion: There is evidence that chronic fatigue syndrome is, in fact, caused by one virus. What is the gap in the reasoning here. We know that the drug has worked on all the symptoms. So we are concluding that all symptoms were caused by one virus. Why? Because we are assuming that the drug likely works on only one virus. A drug could work on many different viruses. So to conlcude that all symptoms were caused by a single virus, we are assuming that this drug works on only one virus. (A) All those who suffer from prolonged fatigue also suffer from neurological problems. We don't have to assume that everyone who suffers from prolonged fatigue also suffers from neurological problems. The two occur together in Chronic fatigue syndrome and that is what we are discussing here. Who else has prolonged fatigue and whether they also have neurological problems is out of scope for us. (B) It is more likely that the new drug counteracts one virus than that it counteracts several viruses. Exactly. This is our assumption. We are assuming that the new drug likely works on one virus, not on several. If we negate it and say that the new drug likely counteracts several viruses then the symptoms could be caused by several different viruses. (C) The symptoms of chronic fatigue syndrome are dissimilar to those of any other syndrome. Irrelevant. We are discussing only chronic fatigue syndrome. Whether another syndrome has similar symptoms doesn't matter to us. Our whole point is whether chronic fatigue syndrome is caused by one virus or several together. (D) Most syndromes that are characterized by related symptoms are each caused by a single viral infection. Irrelevant. How it happens with most syndromes doesn't tell us how it happens with chronic fatigue syndrome. Even if it were to lend some support to our conlcusion, we are looking for an assumption in the question. Do we need this to be true for our conclusion to be true? No. It doesn't matter how most syndromes are caused. (E) An antiviral medication that eliminates the most severe symptoms of chronic fatigue syndrome thereby cures chronic fatigue syndrome. Irrelevant. Whether the medication cures chronic fatigue syndrome or not is out of scope. Answer (B) Discussion on Assumption Questions: https://youtu.be/O0ROJfljRLU A pair of difficult assumption questions: https://youtu.be/ZQnhC4d5ODU

srik410 · Answer

Can someone explain how the likelihood in the assumption translate to confident conclusion of causation?

bb · Answer

We do not need to have a confident conclusion in causation. It just says there is evidence. The answer is not amazing but it is the best of the options available. The easy ideal answer would be "The medication only fixes one virus" or that "medications rarely address multiple viruses" or something like that. Here we have something similar but not quite precise or clear.

There are several ways to solve harder CR questions: 
1. You can prove the path (works great if you can pinpoint the answer and you can clearly spot the correct one)
2. You can eliminate other options because you do not see a better answer, esp. helpful if you don't like the answer you picked.

In this case, you just have to pick the least annoying option, which happens to be B) which is almost a restatement of the argument which is OK - it is the closest thing to the assumption
  
(B) It is more likely that the new drug counteracts one virus than that it counteracts several viruses.

Chronic fatigue syndrome is characterized by prolonged fatigue, muscul

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Chronic fatigue syndrome is characterized by prolonged fatigue, muscul

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards