Maturation of pro-insulin into insulin (simplified) is given below. Select the correct option:
A. A-Proinsulin, B-A peptide, C-B peptide, D-Free C peptide
B. A-A peptide, B-Proinsulin, C-B peptide, D-Free C peptide
C. A-Proinsulin, B-B peptide, C-A peptide, D-Free C peptide
D. A-Free C peptide, B-Proinsulin, C-A peptide, D-B peptide
