Which of the Following Statements Related to Protein Structure Is $\alpha$

Which of the following statements related to protein structure is false?

A) Chaperones may assist in folding proteins.
B) Most of the interactions that stabilize folded proteins are covalent.
C) $\alpha$ -Helical and $\beta$ -sheets are common secondary structures in proteins.
D) Proper folding is essential to the function of a protein.
E) Some proteins contain more than one polypeptide chain.