Answer the following question given this paragraph: 

A protein is an organic compound made up of small molecules called amino acids . There are 20 different amino acids commonly found in the proteins of living things. Small proteins may contain just a few hundred amino acids, whereas large proteins may contain thousands of amino acids.


Q: What is an organic compound made up of small molecules called amino acids called?

 Choices:

- a carbohydrate

- a fat

- a compound

- a protein

A:
a protein
