Self-study
Moore: Sunscreen lotions, which are designed to block skin-cancer-causing ultraviolet radiation, do not do so effectively. Many scientific studies have shown that people who have consistently used these lotions develop, on average, as many skin cancers as those who have rarely, if ever, used them.
3.
The reasoning in Moore's argument is most vulnerable to criticism on the grounds that the argument
a
takes for granted that there are no other possible health benefits of using sunscreen lotions other than blocking skin-cancer-causing ultraviolet radiation
Moore’s argument is only about whether the sunscreen lotions effectively block cancer-causing UV radiation. Whether they have other health benefits is irrelevant.
b
fails to distinguish between the relative number of cases of skin cancer and the severity of those cases in measuring effectiveness at skin cancer prevention
This is true, but it doesn’t weaken Moore’s argument. She argues that sunscreen doesn’t effectively block UV radiation because sunscreen users get skin cancer just as much as non-users. The severity of those cases is irrelevant.
c
fails to consider the effectiveness of sunscreen lotions that are not specifically designed to block skin-cancer-causing ultraviolet radiation
Moore’s conclusion only addresses sunscreen lotions that are specifically designed to block cancer-causing UV radiation. The effectiveness of any other sunscreen lotions is irrelevant.
d
relies on evidence regarding the probability of people in different groups developing cancer that, in principle, would be impossible to challenge
The evidence that Moore cites may not support her conclusion well, but there’s no reason to believe that it would be impossible to challenge.
e
overlooks the possibility that people who consistently use sunscreen lotions spend more time in the sun, on average, than people who do not
Moore concludes that sunscreen is ineffective because both sunscreen users and non-users get the same amount of skin cancer. She overlooks the possibility that there might be some other relevant difference between these groups, like sunscreen users spending more time in the sun.