According to government figures, the rate of people treated for melano

The conclusion of the argument above depends on which of the following assumptions?

A) The increase in the rate of people treated for melanoma did not result from an improved ability to detect the disease at a treatable stage of development.
B) The chances that an individual who contracts melanoma will survive have not improved since 1980.
C) Due to improvements in medical technology, melanoma patients are more likely to live longer after detection of the disease than they were in 1980.
D) It is highly unlikely that medical researchers will discover a cure for melanoma at any time in the foreseeable future.
E) The rate of melanoma will continue to increase unless the government poses a ban on the use of chlorofluorocarbons, which are largely responsible for the destruction of the ozone layer

Hello - GMATNinja abhimahna -

Could you kindly comment on this question. I really don't think - E can be the answer here. My Analysis below -


Assumption is something - which is a must for conclusion to hold true. Also a few of the assumptions of a causal relation (A - caused - B) are -
-- B did not cause A
-- Any thing else did not caused B. (Only A - caused B)

Now coming back to the question -
Argument (summary) - The destruction of ozone layer is the reason behind the increased rate of melanom disease.

Option A is telling - Anything else (i.e. Improvement of detection technique of decease) is not the reason of the increased rate.
Choice E however , talks about a specific chemical - "chlorofluorocarbons" and says unless govt. bans the chemical, rate of melanoma will continue to increase.

Choice E is definitely a strengthener but we can't say it has to be true for conclusion to hold. The reason is use of specific detail on - "chlorofluorocarbons". What if this is not "chlorofluorocarbons" but something else. Choice E - can be considered if it is as shown below -

The rate of melanoma will continue to increase unless the destruction of ozone layer stops, --- Now this needs to be true for the conclusion to hold.

So, A seems to be the clear winner here.