IV. Directions: Copy the letter of the correct answer. 16. It refers to the things, materials or conditions that are varied or changed in the experiment. A. Controlled Variable B. Manipulated Variable C. Responding Variable 17. It refers to the things, materials or conditions that remain constant or the same in the experiment. A. Controlled Variable B. Manipulated Variable C. Responding Variable 18. What refers to the things, materials or conditions that respond to the changes? A. Controlled Variable B. Manipulated Variable C. Responding Variable 19. After the experiment, what material remains constant or the same? A. tin can C. soil D. water 20. After performing the experiment, what material changed? A tin can B. mongo seeds C. soil D. water B. mongo seeds