Answer:
The correct answer is - carbohydrates.
Step-by-step explanation:
The four significant groups of macromolecules found in living beings are carbohydrates, lipids, nucleic acids, and proteins. carbohydrates comprised of carbon, hydrogen, and oxygen molecules, generally in a proportion of 1 : 2 : 1.
Living things use carbohydrates as their main form of energy. Carbohydrates are a class of macromolecules is essentially utilized as a quickly accessible energy source by living things.
Thus, the correct answer is - carbohydrates.