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: Medicine
[{'content': 'The most common cause for chronic cor pulmonale is \nSelect and explain. \nA. Recurrent pulmonary embolization, B. COPD, C. Cystic fibrosis, D. Bronchial Asthma', 'role': 'user'}, {'content': "Answer: B \nExplanation: Answer is B (COPD): The most common cause of chronic cor puhnonale is chronic. obstructive pulmonary disease - Rubin's pathology", 'role': 'assistant'}]