One gram of carbohydrate, one gram of lipid, and one gram of protein yield ________, ________, and ________ kilocalories respectively.

A) 4, 4, 4
B) 9, 9, 9
C) 4, 9, 4
D) 4, 9, 9
E) 9, 9, 4

Lipid

Substance composed principally of carbon, oxygen, and hydrogen; contains a lower ratio of oxygen to carbon and is less polar than carbohydrates; generally soluble in nonpolar solvents.

Carbohydrate

Monosaccharide (simple sugar) or the organic molecules composed of monosaccharides bound together by chemical bonds—for example, glycogen. For each carbon atom in the molecule, there are typically one oxygen molecule and two hydrogen molecules.