HUMAN NUTRITION

Detailed explanation-1: -So, the correct answer is Lipids.

Detailed explanation-2: -Carbohydrates are a group of macromolecules that are a vital energy source for the cell, provide structural support to many organisms, and can be found on the surface of the cell as receptors or for cell recognition.

Detailed explanation-3: -Macromolecules : Example Question #4 There are four classes of biological molecules: fats, carbohydrates, proteins, and nucleic acids. Of these, fats produce the most energy per gram at a whopping nine calories per gram. Carbohydrates and proteins produce less than half of this, at only four calories per gram.