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: Pediatrics
[{'content': 'Most Common cardiac tumor in childhood ? \nSelect and explain. \nA. Rhabdomyoma, B. Lymphoma, C. Atrial myxoma, D. Sarcoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most Common primary cardiac tumor in infancy and childhood is Rhabdomyoma. Ref : Harrison principals of internal medicine, 19th edition,chapter289e,p.no:1577', 'role': 'assistant'}]