An Experiment Examined the Psychophysiological Effect of THC, the Active

An experiment examined the psychophysiological effect of THC, the active ingredient in marijuana. The study recruited a sample of 18 young adults who were habitual marijuana smokers. Subjects came to the lab three times, each time completing the same questionnaire, but each time smoking a different marijuana cigarette: one with 3.9% THC, one with 1.8% THC, and one with no THC (a placebo) . The order of the conditions was randomized in a double-blind design. Why can we not use a one-way ANOVA procedure here to test whether the mean "feeling of high" is the same for all three THC amounts?

A) The assumption of independent random samples is not met.
B) The assumption of Normality is not met.
C) The assumption of equal population standard deviations is not met.
D) The explanatory variable is categorical.