Which is a difference between proteins and carbohydrates and fats?

• A. Proteins are composed of monomers; carbohydrates and fats are not.
• B. Excess carbohydrates and fats are stored; excess proteins are not.
• C. Proteins are macromolecules; carbohydrates and fats are not.
• D. Carbohydrates and fats contain carbon, hydrogen, and oxygen; proteins do not.