The correct answer is: B. amino acids
Proteins are biopolymers made up of amino acids. Amino acids are the building blocks of proteins, and they are linked together by peptide bonds to form polypeptide chains. The sequence of amino acids in a polypeptide chain determines the protein’s structure and function.
Carbohydrates are another type of biopolymer, but they are made up of sugar molecules. Sugar molecules are linked together by glycosidic bonds to form polysaccharides. Polysaccharides are used for energy storage and structural support.
Fatty acids are lipids, and they are not used to build proteins. Fatty acids are made up of carbon and hydrogen atoms, and they are linked together by ester bonds to form triglycerides. Triglycerides are used for energy storage and insulation.
Alkenes are hydrocarbons, and they are not used to build proteins. Alkenes are made up of carbon and hydrogen atoms, and they are linked together by double bonds. Alkenes are used as fuels and in the production of plastics.