Zelda is interested in testing the effectiveness of a new flea medication on dogs, so she divided some dogs with fleas into two groups, group B and group C. She gave group B the flea medication. Should she also give group C the flea medication? A. Yes, because group C should be the control group. B. Yes, because group B is already the control group. C. No, because group B is already the control group. D. No, because group C should be the control group