This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pharmacology
[{'content': 'True about vitamin K is: \nSelect and explain. \nA. It is required for synthesis of factor VII, B. Long term use of antimicrobials can cause deficiency of vitamin K, C. It is a water soluble vitamin, D. DVT is associated with vitamin K deficiency', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (B) Long term use of antimicrobials can cause deficiency of vitamin K(Ref: KDT 8/e p661)Vitamin K is involved in activation of factor II, VII, IX and X (not synthesis)It is a fat soluble vitamin like Vitamin A, D and E. Vitamin B and C are water soluble.Warfarin (an inhibitor of vitamin K) is used for treatment of DVT.Long term antimicrobial use can alter gut flora leading to deficiency of vitamin K.', 'role': 'assistant'}]