Here, the main argument is that zinc gel applied nasally is more effective in curing cold than zinc lozenges because the cold viruses tend to concentrate in the nose more than the mouth. If we are to weaken this argument, then we need to show that zinc lozenges and zinc gel are different even though they contain zinc in the same proportion.

Choice A compares zinc gel to other gels which do not contain zinc, hence irrelavant.
Choice B talks about mechanism by which zinc affects viruses which is not discussed in the argument.
Choice C shows that zinc lozenges are different from zinc gel in that they have other ingredients which may interfere with chemical activity of zinc. This is relevant and weakens the main conclusion.
Choice D talks of time within which the cold is treated with the zinc medicine which is again irrelevant.
Choice E only shows that zinc applied nasally is very effective hence strengthening the argument of the author.

Therefore, C.

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As Birottam says, A introduces gels without the zinc. The comparison in the stimulus is between zinc gels and zinc lozenges, so A is out of scope.

IMO C

The conclusion states that zinc gel is more effective than zinc lozenges because the gel is applied nasally.

Option C weakens the argument. It provides a different reason for effectiveness of the gel when compared to zinc lozenges. The lozenges have additional ingredients that reduce its effectiveness.

C for me too!

Though sucking zinc lozenges has been promoted as a treatment for the common cold, research has revealed no consistent effect. Recently, however, a zinc gel applied nasally has been shown to greatly reduce the duration of colds. Since the gel contains zinc in the same form and concentration as the lozenges, the greater effectiveness of the gel must be due to the fact that cold viruses tend to concentrate in the nose, not the mouth.


Which of the following, if true, most seriously weakens the argument ?

A Experimental subjects who used the zinc gel not only had colds of shorter duration but also had less severe symtoms than did those who used a gel that did not contain zinc.

B The mechanism by which zinc affects the viruses that cause the common cold has not been conclusively established.

C To make them palatable, zinc lozenges generally contain other ingredients, such as citric acid, that can interfere with the chemical activity of zinc.

D No zinc-based cold remedy can have any effect unless it is taken or applied within 48 hours of the initial onset of cold symptoms.

E Drug-company researchers experimenting with a nasal spray based on zinc have found that it has much the same effect on colds as the gel does.




This is a causal reasoning with comparison question. Normal zinc lozenges do not affect or help to cure common cold but when applied the gel having zinc, then it helps cure common cold. Hence the stimulus says that the reason for the cure of common cold is the gel that is applied at the nose and hence maximum germs are present in the nose and not in the mouth.

So if you want to weaken this question see the options:

Option A: Comparison between cold for longer duration and shorter duration. Out of scope not valid.

Option B: We are not concerned with the mechanism. Even if we are concerned with the mechanism it does not differentiate between zinc lozenges and zinc gel. Hence not affecting the argument and hence Out of scope

Option D: Again talking overall of all the zinc based products or medicine. Not talking or differentiating about between zinc gel or zinc lozenges.

Option E: Again out of scope as we are not talking about nasal spray based on zinc...


Option C is the perfect negation to the argument or the causal argument.

I would go for the option C and am sure that the OA is C.

Hope this helped...

A classic causal argument!
Keep sharing such g8 Qs
Regards,
Mukherjee

IMO C. No doubt.
A is irrelevant.

bryan88 wrote:Though sucking zinc lozenges has been promoted as a treatment for the common cold, research has revealed no consistent effect. Recently, however, a zinc gel applied nasally has been shown to greatly reduce the duration of colds. Since the gel contains zinc in the same form and concentration as the lozenges, the greater effectiveness of the gel must be due to the fact that cold viruses tend to concentrate in the nose, not the mouth.


Which of the following, if true, most seriously weakens the argument ?

A Experimental subjects who used the zinc gel not only had colds of shorter duration but also had less severe symtoms than did those who used a gel that did not contain zinc.

B The mechanism by which zinc affects the viruses that cause the common cold has not been conclusively established.

C To make them palatable, zinc lozenges generally contain other ingredients, such as citric acid, that can interfere with the chemical activity of zinc.

D No zinc-based cold remedy can have any effect unless it is taken or applied within 48 hours of the initial onset of cold symptoms.

E Drug-company researchers experimenting with a nasal spray based on zinc have found that it has much the same effect on colds as the gel does.