NEET Biology question

Which of the following statements regarding the structure of proinsulin and mature insulin are not correct?

1. Proinsulin is made up of three polypeptide chains – A, B and C. 2. C-polypeptide chain with 33 amino acids is removed prior to insulin formation. 3. Mature insulin is made up of 51 amino acids arranged in two polypeptide chains – A and B. 4. Polypeptide chain A has 30 amino acids and polypeptide chain B has 21 amino acids. 5. Polypeptide chains A and B are interconnected by only one S – S linkage.

• (A)(i) and (ii)
• (B)(iii) and (iv)
• (C)(iv) and (v)Correct
• (D)(iii), (iv) and (v)