This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
Recent oral direct thrombin inhibitor which can be used for prevention of stroke is 
Select and explain. 
A. Dabigatrin, B. Ximelagatran, C. Lepirudin, D. Saxagliptin
B: Ximelagatran
Answer: B: Ximelagatran 
Explanation: Refer Katzung 11/e p 594 Ximelagatran was the first viral direct thrombin inhibitor approved, however it was later withdrawn because of hepatotoxicity. Recently a new direct thrombin inhibitor Dabigatrin had been approved for the prophylaxis of stroke and systemic embolism in nonvalvular atrial fibrillation