A new study provides more support for the hypothesis that

A new study provides more support for the hypothesis that social support may strengthen people’s immune system. This study actually found that social isolation and loneliness can impair the immune system. According to the findings of the study, lonely and socially-isolated first-year students mounted a weaker immune response to the flu shot than other students.

The argument is flawed primarily because

The problem IMO relies in the red part of the text. In the first part the conclusion of the study is presented, and then it is said that, according to the conclusion, lonely students have a weaker immune system. Before reading the answers it's clear that a weak point is the fact that other factors can contribute to this condition.

IMO B
(B) it assumes that a necessary condition for an event is a sufficient condition for that event to occur
It says that a necessary condition ( loneliness) for an event (weak system) is a sufficient condition (no other factors involved).

Waiting for OA...

Hi

here B is wrong because neither is stated explicity nor implied about sufficiency and so on.....

C instead basically says that if you are alone, this scenari leads to an unbalance immune system but if you have the latter is not true that you have the first scenario (loneliness).

OR

Just because the cause is removed does not mean the effect will get reversed. It might remain unchanged.

C is the OA indeed

A new study provides more support for the hypothesis that social support may strengthen people’s immune system. This study actually found that social isolation and loneliness can impair the immune system. According to the findings of the study, lonely and socially-isolated first-year students mounted a weaker immune response to the flu shot than other students.

The argument is flawed primarily because

(A) it assumes that there can only be one cause for an effect
Nowhere is this stated or implied so this cant be the answer

(B) it assumes that a necessary condition for an event is a sufficient condition for that event to occur
The argument is not saying that loneliness is the necessary condition for a weaker immune system so this choice us also eliminated.

(C) it assumes that if a cause for an effect is removed, then the effect will in turn get reversed
This is closest to the argument in the passage as students who are not isolated (other students) don’t have a weaker response to flu shots.
But this should not mean that if loneliness is removed than the immune system will get ok and hence this is the flaw in the reasoning
(D) it mistakes a symptom for a cause
Cause is isolation and loneliness so this option is not possible.
(E) it is based on unverified and subjective data
Nowhere is it said that the data is unverified.

+1 C
Rephrasing the argument -
A study - 'lonely and socially-isolated students -- > a weaker immune response' provides support for the hypothesis - 'Social support may strengthen people’s immune system' -- clearly indicates the flaw because it assumes that if a cause (social isolation) for an effect (Weak immune system) is removed, then the effect will in turn get reversed

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The argument is flawed because it assumes there cannot be other reasons which can cause the same effect.

Both A and C says the same. How can C) be OA?

Argument says 'This study actually found that social isolation and loneliness can impair the immune system'

A) it assumes that there can only be one cause for an effect

No, it doesn't assume that in any way. It just says social isolation and loneliness CAN impair the immune system. Whereas, what you are saying would be a paraphrase of 'This study actually found that ONLY social isolation and loneliness can impair the immune system'

I picked C as it was the closest, but a bit borderline imo. The cause for effect is not only removed, but also reversed (as is the effect). Maybe in logic terms, these two are equivalent...

I am confused on why not A. The stem says

According to the findings of the study, lonely and socially-isolated first-year students mounted a weaker immune response to the flu shot than other students

Isn't this assuming that social isolation could be the only cause for these students to have weaker immune response

Here is my approach.

Lets identify the cause and effect in the argument.

Cause: Social isolation

Effect: Weaker immune system

Based on this cause-effect relationship, the argument concludes that social support strengthens immune system.

So the conclusion basically assumes that if cause is removed (or social support is improved), then the effect will be reversed (immune system will be strengthened).

Hence C is the answer.

The second line in argument -"This study actually found that social isolation and loneliness can impair the immune system." - this line is basically derived by negating the result given in first line that social support sttengthens the argument. And then the study conducted on first year students has given to substantiate the claim that since social support system was absent,the students showed weaker immune response. 2 things to note here :

1. Line 2 is negation of line 1. However this is not correct. Absence of social support system doesn't imply that effect will also get reversed i.e. weak immune system. What if immune system remains same?
2. The study's result is then used to justify the misinterpreted conclusion that students showed weaker reponse because they did not have social support system. It is possible that weak immune system was due to some other reason and not really social support eg. Say, they were not eating properly and hence their immunity was impacted. It can be just a coincidence those students were also socially isolated.

If #2 is valid, then isn't A also logical flaw?

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