Baby rabbits were sorted into three groups, based upon which food they preferred when given a choice: Brand A rabbit food, Brand B rabbit food, or a diet of raw vegetables. For two months each group was restricted to their preferred diet (they were no longer given a choice in diet). Measurements for the height, weight, and length of the rabbits was taken each week for two months. The rabbits in the group with the diet of raw vegetables had significantly more growth that the other two groups. What conclusion can be drawn from this study?
