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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Commonest cause of Budd Chiary syndrome is:
assistant
The correct answer is  Answer is C (Paroxysmal nocturnal hemoglobinuria): The most common cause of hepatic vein thrombosis from the list mentioned in Harrison is Paroxysmal nocturnal hemoglobinuria, and hence is the answer of choice here.