Identify the wring statement with reference to the structure of human insulin

Options

A. Insulin is synthesised as a pre-hormone which contains an extra stretch called C-peptide
B. A and B chains are combined by disulphide bonds to form humulin
C. Human insulin is made up of 51 amino acids arranged in two polypetide chains
D. In these, chain A is made up of 30 amino acids and chain B is made up of 21 amino acids.

Answer

D