Question

Item 6The organic compounds in living things are organized into groups: carbohydrates, lipids, proteins, and nucleic acids.Which two compounds do living things most commonly use as an energy source?a. carbohydrates and lipidsb. proteins and nucleic acidsc. lipids and nucleic acidsd. proteins and carbohydrates

Answer 1

So, considering that, carbohydrates and lipids are the most commonly used biomolecules for energy sources. We could mention that the amount of energy obtained from these two organic compounds is 4 kilocalories/gram (kcal/g), and 9 kcal/g, respectively.

So the answer to the question is the a point:

carbohydrates and lipids.