Support To test the claim that vitamin C is effective in treating acne, scientists administered it to one group of subjects and a placebo to a control group. ███ █████ █████████ ███████ █ ███ ████ ██████ ████ ██████ ███ █████ ████ ███ ███ ███████ ██████ ██ ███ ████████████ ███████████ ████████ ████ ████ ██ ███ ████████ ██ ████ █████ ████ █████ ████ ██ ████ ████ ████ ██████ █████ █████ ███ █████ ███ █████ ██ ██████████ ██ ███ ████████ ██ ████ ███ █████ ███████ ███ ███ ███████ ██████████ ██ ███ ███████████ ████████ ████ ███████ █ ███ ██ ████ ███████ ██ ████████ ███ ████████ ██ █████
The author hypothesizes that vitamin C does not help reduce the severity of acne. This is based on a study showing no difference in the severity of acne between a group given vitamin C and a control group given a placebo.
The argument assumes that there were no differences between the vitamin C group and the control group that could have made the vitamin C group’s acne more severe, thus masking the beneficial effect of vitamin C. The argument also assumes that before the study began, the vitamin C group did not start with more severe acne than the control group, which is another way beneficial effects of vitamin C could have been masked.
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