4-Hydroxyproline, a nonstandard amino acid derived from proline, is essential for stabilizing the triple helix structure of collagen.
| List-I | List-II |
|---|---|
| (I) Vitamin C | (A) Thiamine |
| (II) Vitamin B1 | (B) Riboflavin |
| (III) Vitamin B6 | (C) Ascorbic Acid |
| (IV) Vitamin B2 | (D) Pyridoxine |