If the Digestive Systems of Animals Are to Provide the Energy

If the digestive systems of animals are to provide the energy needed for ATP and biosynthesis, which of the following diets would be most suitable?

A) a high protein, low carbohydrate diet
B) a diet low in lipids and high in protein
C) a low-calorie diet with large intake of fluids, especially water
D) a diet that matches the "food pyramid" for the species
E) a diet that maximizes vitamins and minerals