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: Pediatrics
[{'content': 'All are a major manifestation of rheumatic fever and rheumatic heart disease except \nSelect and explain. \nA. Carditis, B. Elevated antiistreptolysin-O, C. Polyarthritis, D. Erythema marginatum', 'role': 'user'}, {'content': 'Answer: B \nExplanation: major criteria of RHD include card it is,chorea,arthritis, subcutaneous nodule, erythema marginatum', 'role': 'assistant'}]