A student is studying insulation used to keep houses warm. The student builds 10 model houses and uses a different thickness of insulation on each house. She then measures the temperature inside each model house. Which statement correctly describes a variable in this experiment?
A. The thickness of the insulation is the variable that responds to the
temperature.
B. The temperature is the variable that responds to the number of houses.
C. The number of houses is the variable that responds to the temperature of the house.
D. The temperature is the variable that responds to the thickness of the insulation.