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
The Similarity between Vit C & Vit K is : 
Select and explain. 
A. Both help in conversion of proline to hydroxy-proline, B. Both help in post-translational modification, C. Both have anti infective activity, D. Both are involved in coagulation cascade
B: Both help in post-translational modification
Answer: B: Both help in post-translational modification 
Explanation: B i.e. Both help in post translational modification