This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Valvular hea diseases, Subject name: Medicine
[{'content': 'A patient with angina, exeional syncope and Left ventricular hyperophy is diagnosed with aoic stenosis. What is the predicted life span of this patient? \nSelect and explain. \nA. 1 year, B. 2 years, C. 3 years, D. 4 years', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Predicted life span based on symptoms in patients of aoic stenosis Angina and exeional syncope :3 years Dyspnea :2 years CHF : 1.5 years', 'role': 'assistant'}]