Which analysis best explains why dietary fat is more efficient for long-term energy storage than carbohydrate?

• A. Fat contains more than twice the kcal per gram than carbohydrate, so storing energy as fat requires less mass and is metabolically efficient for long-term storage.
• B. Fat and carbohydrate have identical energy densities but fats are preferred for storage because they are converted to glycogen more rapidly in the liver than carbs are.
• C. Protein is the primary molecule for long-term energy storage because it provides structural benefits and can be mobilized without fluid balance consequences, whereas fat cannot be efficiently stored.
• D. Carbohydrate has a higher energy density than fat and therefore is stored preferentially over fat because it preserves water balance and cell membrane integrity.

Answer: (A)