Answer: B. Both are sources of cellular energy.
Step-by-step explanation:
Carbohydrates and lipids both are the biomolecules which are composed of carbon, hydrogen and oxygen in different proportions. The lipids have greater ratio of hydrogen to oxygen than that of carbohydrates. The lipid molecules contain more energy per gram of the carbohydrates. These are sources of energy in the body and provides energy for functioning of the cellular metabolism.