This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood: Hemostasis and Blood Coagulation, Subject name: Physiology
The biochemical role of vitamin K in the post- translational modification of clotting factors is by? 
Select and explain. 
A. Glycosylation, B. Carboxylation, C. Acetylation, D. Phosphorylation
B: Carboxylation
Answer: B: Carboxylation 
Explanation: Ans. (b) CarboxylationVitaminActionsDeficiency SynptomesSourcesK groupCatalyze g carboxylation of glutamic acid residues on various proteins concerned with blood clottingHemorrhagic phenomenaLeafy green vegetables