A recent study that compared most physiological processes of the menta

Question

A recent study that compared most physiological processes of the mentally ill to those of the mentally healthy discovered that persons with minor mental illness are more likely to have sleep disorders than those who are mentally healthy. Such research provided grounds for some scientists to speculate that minor mental illness often causes sleep disorders.

Which of the following, if true, most weakens the speculation above?

(A) Some persons with minor mental illness do not have sleep disorders.
(B) Those with minor mental illness are more subject to infectious diseases than mentally healthy persons are.
(C) Sleep disorder is often caused by certain nerve-stimulating drugs or by extreme stress.
(D) Persons with sleep disorders often develop minor mental illness.
(E) Persons without mental illness sometimes have sleep disorders.

In absence of (D), can (C) be a possible answer since it is another possible cause for an effect?

Source: Optimus Prep

nikhiljd · Answer

D is the answer ... reversal of causality ... ?

nishith17 · Answer

Yes, D it is. In absence of (D), can (C) be a possible answer since it is another possible cause for an effect?

Archit143 · Answer

Hello C, cannot be answer because it has word "often". Moreover it says sleep disorder is caused by some other reason but does not hints or relates to mental health. In absence of D it can be answer but please avoid such kind haggling because this is not correct way to approach. What you must be knowing is why is D not a correct answer?

Hit Kudos if you like my explanation! Hope it helps!

-AA

sowragu · Answer

In a weaken question like this,

A Causes B -- Weaken the statement --> B is the cause of A.

Mental illness cause sleep disorder --> Weaken --> Sleep disorder cause mental illness.

chesstitans · Answer

this is a common pattern about causal relation and the correlation.

Bombsante · Answer

Hi guys,
I am not able to grasp why options E & A are not the correct answers.
Can someone help? Expert's take would be welcome.

Abhishek2226 · Answer

Why C is not considered as the correct answer ?
As to weaken a Causal Argument, we can definitely show that some other reason which is causing the effect to happen ... Please explain someone ... This facts are disturbing

shahkevin99 · Answer

Can someone please explain this question more accurately.

Mansoor50 · Answer

Am no expert but i did get confused too.
A/D/E all seem to weaken

A. there is the Cause (mental illness) but no effect (Sleep disorder SD) - but here the keyword is "some" in the answer choice....i treated it as an outlier case ... in that sure....statistically this will be there

D. uses "often" which is also used in the speculation in the stem

E. the word "sometimes" made me throw this away too...even tho there is Effect w/o the cause

thats how i chose D

hientranzx · Answer

A recent study that compared most physiological processes of the mentally ill to those of the mentally healthy discovered that persons with minor mental illness are more likely to have sleep disorders than those who are mentally healthy. Such research provided grounds for some scientists to speculate that minor mental illness often causes sleep disorders.

Conclusion:   mental illness --> sleep disorders.

Which of the following, if true, most weakens the speculation above?

(A)  Some persons  with minor mental illness do not have sleep disorders.
Some persons only
(B) Those with minor mental illness are more subject to  infectious diseases  than mentally healthy persons are.
infectious diseases is not relevant
(C) Sleep disorder is often caused by certain  nerve-stimulating drugs or by extreme stress .
nerve-stimulating drugs or by extreme stress: Irrelevant
(D) Persons with sleep disorders often develop minor mental illness.
 sleep disorders --> minor mental illness (Not: mental illness --> sleep disorders) 
This is the correct answer.
(E) Persons  without mental illness  sometimes have sleep disorders.
without mental illness: Irrelevant

JoeKan1234 · Answer

A recent study that compared most physiological processes of the mentally ill to those of the mentally healthy discovered that persons with minor mental illness are more likely to have sleep disorders than those who are mentally healthy. Such research provided grounds for some scientists to speculate that minor mental illness often causes sleep disorders.

Which of the following, if true, most weakens the speculation above?

(A) Some persons with minor mental illness do not have sleep disorders.
(B) Those with minor mental illness are more subject to infectious diseases than mentally healthy persons are.
(C) Sleep disorder is often caused by certain nerve-stimulating drugs or by extreme stress.
(D) Persons with sleep disorders often develop minor mental illness.
(E) Persons without mental illness sometimes have sleep disorders.

D is better than C. C is questionable. How can we know whether the subjects in the experiment suffered from nerve-stimulating drugs or extreme stress? The passage doesn't provide relevant information. Therefore, C isn't necessarily a weakener.

D reverses the causal relationship. Correct.

A recent study that compared most physiological processes of the menta

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A recent study that compared most physiological processes of the menta

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

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