Q27:

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.

In order to evaluate the argument, it would be most helpful to determine which of the following?

1. Whether zinc is effective only against colds, or also has an effect on other virally caused diseases
2. Whether there are remedies that do not contain zinc but that, when taken orally, can reduce the duration of colds
3. Whether people who frequently catch colds have a zinc deficiency
4. Whether either the zinc gel or the lozenges contain ingredients that have an impact on the activity of the zinc
5. Whether the zinc gel has an effect on the severity of cold symptoms, as well as on their duration

I prefer B although the reference answer is D

In my opinion that author tell us that since the same concentration and form is applied in both medicine taken orally and nasally,it seems logically to infer that the discrepancy in the treatment results is due to the conslusion made by author various tend to concentrate in nose only.

If the description above is true,the conclusion will be undermined by the fact that another unkonw drugs taken orally has effect on the cold.

In choice D,the ingredients have an impact on the activity of the zinc seems to say the reason why the drugs contain the zinc have the effect on the cold.That is far from the argument I think .If the answer is yes,the conlusion that different region alluded for different results in cold treatment is still there wihout any support nor weaken.

open to discuss

I agree with D.

since the possible remedies don't contain Zinc, it doesn't make sense to compare them with lozenges or gel.