Question

a carbohydrate is a
a. fat molecule.
b. molecule used to store energy.
c. a chemical reaction used to create energy.
d. measurement of how much energy is stored in food.

Explanation:

• Option A: Carbohydrates and fat molecules are different types of biomolecules, so A is incorrect.
• Option B: Carbohydrates are organic molecules (like sugars, starches) that are a primary source of energy and can be used to store energy (e.g., glycogen in animals, starch in plants), so this is correct.
• Option C: A carbohydrate is a molecule, not a chemical reaction, so C is incorrect.
• Option D: A measurement of energy in food is calorie, not a carbohydrate, so D is incorrect.

Answer:

B. molecule used to store energy.