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': 'Gradient in pulmonary artery wedge pressure and left venticular end diastolic pressure is seen in \nSelect and explain. \nA. Aortic regurgitation, B. Constrictive pericarditis, C. Left atrial myxoma, D. Pulmonary thromboembolism', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]