This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'The commonest intracavitary benign cardiac tumour is \nSelect and explain. \nA. Leiomyoma, B. Myxoma, C. Sarcoma, D. Lipoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Myxoma, a benign tumor, is the most common type of primary cardiac tumor. Cardiac tumors may occur in any cardiac tissue. They can cause valvular or inflow-outflow tract obstruction, thromboembolism, arrhythmias, or pericardial disorders. Diagnosis is by echocardiography and frequently cardiac MRI. Ref Davidson 23rd edition pg 455', 'role': 'assistant'}]