Valerie and Greg want to bake a cake. They mix the cake batter and preheat the oven. Once the oven reaches the right temperature, they pour the batter in a cake pan, put it in the oven, and close the door. They know that while the cake is in the oven, a chemical change that involves energy occurs. Which of these statements describes the amount of energy in the oven while the cake is baking?
A. The total amount of energy will either increase or decrease, depending on how much cake batter there is.
B. The total amount of energy increases because the oven gets very hot.
C. The total amount of energy decreases because it changes into matter.
D. The total amount of energy stays the same, but it changes from one form to another.