This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Minerals, Subject name: Biochemistry
[{'content': 'Vitamin K dependent clotting factors are: \nSelect and explain. \nA. Factor III & XI, B. Factor IX & X, C. Factor V & VIII, D. Factor XI & XIII', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Vitamin K is the cofactor for g-carboxylation of glutamate residues of the proteins to produce g carboxy glutamate (gla)- Clotting factors contain 4 to 6 g-carboxyglutamate residues Eg- II VII IX X Protein C Protein S Protein Z Osteocalcin Transthyretin (Prealbumin)', 'role': 'assistant'}]