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: Pathology
[{'content': 'The most common site for myocardial infarction is - \nSelect and explain. \nA. Left atrium, B. Left ventricle, C. Right atrium, D. Right ventricle', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]