Stacked Attempt 4 People who eat lots of fruits and vegetables have lower rates of colon cancer than those who eat little of these foods. Fruits and vegetables are rich in antioxidants such as vitamins A, C, and E. Will taking antioxidants help prevent colon cancer? A ect medical experiment studied this question with 864 people who were at risk of colon cancer. The subjects were divided into four groups: daily beta-carotene, daily vitamins C and E, all three vitamins every day, or daily placebo. After four years, the researchers were surprised to find no significant difference in colon cancer anlong the groups. rect The study is described in Gina Kolata, "New study finds vitamins are not cancer preventers," New York Times, July 21, 1994. Look in the Journal of the American 5% Medical Association of the same date for the details. rect 00% rrect What are the explanatory and response variables in this experiment? 0% Progress Explanatory variable(s) Response variable(s) 100%