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 one of the following is direct thrombin inhibitor: \nSelect and explain. \nA. Enoxaparin, B. Dalteparin, C. Fondaparinux, D. Argatroban', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Argatroban', 'role': 'assistant'}]