Answer & explanation:
When we refer to macronutrients, we talk about proteins, carbohydrates and lipids.
In a meal, carbohydrates are usually in greater quantity than proteins and fats, and are primarily used as fuel for metabolic processes.
Carbohydrates have on average 4 kcal per gram (or 17 kJ/g), proteins also have 4 kcal/g, but fats are approximately 9 kcal per gram (or 37 kJ/g).
Thus, fats have a higher energy charge compared to proteins and carbohydrates, although they are not primarily used as cellular fuel.