Which of the following is a function of carbohydrates?

• A. Energy production, storage and cell structure
• B. Cooling the body by sweating
• C. Structural support in proteins
• D. Acting as enzymes

Answer: (A)

Carbohydrates mainly provide quick energy for cells and can be stored for later use, with glycogen serving as the storage form in animals and starch in plants. They also contribute to cell structure in certain contexts, such as cellulose in plant cell walls. This combination—energy production, storage, and a structural role in cells—best fits the function described. The other options describe processes not typically carried out by carbohydrates: cooling the body by sweating is a thermoregulation mechanism, structural support in proteins is a role of proteins themselves, and enzymes are usually proteins (or occasionally RNA), not carbohydrates.