Which of the following is an organic molecule needed by the body in small amounts?

The correct option is C Vitamin-C

Vitamin C is a water soluble vitamin needed to be taken into the body in small amounts. Vitamin C is therefore categorised as a micronutrient. All the others mentioned here, i.e., proteins, lipids and monosaccharides are macronutrients. They are required by the body in large quantities for supply of energy and as building blocks in the body. Monosaccharides like glucose molecules are the primary source for energy in the body.