Protein is:. a. unique in that it is the only dietary component that contains oxygen.
b. important primarily because it builds strong bones and teeth.
c. made up of 20 different amino acids.
d. made up of branches of amino acids combined with branches of glucose.

c. made up of 20 different amino acids.

Explanation:

Protein are macromolecules which have long chains of amino acids and they are used in the production of enzymes and aids metabolic activities of the body such as in the repair of worn out tissues and building up of muscle mass.

Protein is unique as it contains about 20 different amino acids. Carbohydrates also have Oxygen present in their compound. Calcium is the mineral responsible for building up of bones and teeth.