This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Post translational modification of lysine and proline is by 
Select and explain. 
A. Vit A, B. Vit C, C. Vit B1, D. Vit D
B: Vit C
Answer: B: Vit C 
Explanation: None