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