What is the main difference between a polypeptide and a protein?

• A. Polypeptides are shorter chains of amino acids, while proteins are longer chains.
• B. Polypeptides refer to chains of amino acids, while proteins refer to chains in their functional form.
• C. Polypeptides are functional, while proteins are not.
• D. Polypeptides contain only hydrophobic amino acids, while proteins contain hydrophilic amino acids.

Answer: (B)