The correct answer is "metabolism." The chemical process by which your body breaks down nutrients in food to release energy for the cells is called metabolism. To arrive at this answer, you can analyze the given options and eliminate those that are unrelated. In this case, "cholesterol" and "nutrition" are not directly related to the process of breaking down nutrients for energy. Additionally, "calories" should be mentioned once, not twice, as it is a unit of energy measurement and not the process itself. By process of elimination, you are left with "metabolism" as the correct answer.
