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': 'High output cardiac failure is seen in: \nSelect and explain. \nA. Thyrotoxicosis, B. Congestive cardiac failure, C. Corpulmonale, D. Aortic stenosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]