50 POINTS !! Question 19 of 25 How is a controlled variable different from a responding variable? OA. A controlled variable stays the same due to changes in the responding variable during the experiment. B. A controlled variable stays the same throughout an experiment, but a responding variable changes. OC. A controlled variable changes due to changes in the responding variable during the experiment. D. A controlled variable changes throughout an experiment, but a responding variable stays the same. ​