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