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: Pharmacology
[{'content': 'Which of the following drugs should not be administered concomitantly with warfarin as it decreases the effect of oral anticoagulants \nSelect and explain. \nA. Broad spectrum antibiotic, B. Cimetidine, C. Aspirin, D. Oral contraceptive', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Oral contraceptives Estrogen increases the synthesis of various clotting factors and produce a hypercoagulable state. Thus OCP containing estrogen decrease the effectiveness of warfarin and other oral anticoagulants.', 'role': 'assistant'}]