dimmak wrote:
According to government figures, the rate of people treated for melanoma, a deadly form of skin cancer, has increased dramatically since 1980. These statistics prove that efforts to halt the destruction of the ozone layer, which serves to filter out the cancer-causing ultraviolet rays of the sun, have been largely unsuccessful.
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.
Premise : rate of people treated for melanoma has increased dramatically since 1980.
Conclusion: The statistics proves that efforts to halt the destruction of ozone layer have largely been unsuccessful.
Let's try to find the ways in which the conclusion is weakened given the premise.
How to get conclusion to weaken(pre-thinking):
1. What if the rate for people being treated was low because there was no way for anyone to find out if someone had melanoma until it was too late.
2. What if there are multiple reasons for melanoma and destruction of ozone is only one.
If these are true, then the statistics do not prove that the efforts to halt the destruction of ozone layer have been unsuccessful.
Hence, the assumptions are :
1. The increase in rate of people in whom the melanoma was detected in earlier stages was not improved.
2. Melanoma can only caused by harmful rays from sun and not anything else, say tanning machine.
The answer is definitely A.
Looking at E.
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.
How is a conclusion that is trying to prove something based on past result be assuming something from future ? That totally nonsensical.