Calorie expenditure is best described as

• A. Calories you burn through physical activity
• B. Calories you eat in a day
• C. Calories you burn through physical activity and metabolism
• D. Calories consumed during meals

Answer: (C)

Energy expenditure represents the total calories your body uses in a day. It comes from two main sources: metabolism—your body's energy use for basic functions at rest—and physical activity—the extra energy burned when you move. The option that includes both physical activity and metabolism best captures this total. Focusing only on activity ignores the energy your body uses just to keep you alive, while talking about calories you eat or meals describes intake, not expenditure.