Small molecules are used as the basic units in the synthesis of large food molecules.
Which statement is correct?

- Amino acids are the basic units of proteins, not carbohydrates.
- Fatty acids are not the basic units of glycogen; glucose molecules are the basic units of glycogen.
- Glycerol is a component of lipids (fats and oils), and it can combine with fatty acids to form triglycerides, which are the main constituents of oils.
- Simple sugars (monosaccharides) are the basic units of carbohydrates, not proteins.
So, the correct answer is that glycerol is a basic unit of oils.