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: Medicine
[{'content': 'A 10 year old boy, Pappu, died of acute rheumatic fever. All the following can be expected at autopsy except : \nSelect and explain. \nA. Ashoff nodules, B. Rupture of chordae tendinae, C. Mc Callum patch, D. Fibrinous pericarditis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Answer is B (Rupture of Chordae tendinae)', 'role': 'assistant'}]