Answer:
D. Lipids
Explanation:
A lipid is any of various organic compounds that are insoluble in water. They include fats, waxes, oils, hormones, and certain components of membranes and function as energy-storage molecules and chemical messengers.
Lipids are an efficient source of energy (9kcal per gram) that the body stores in relative abundance. They also play an important role as building blocks for cell membranes, hormones, and physiologically active substances.
