This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tonsils, Subject name: ENT
[{'content': "Patch on tonsil is not caused by: \nSelect and explain. \nA. Vincent's angina, B. Candida, C. Staphylococcus, D. Ludwig's angina", 'role': 'user'}, {'content': "Answer: D \nExplanation: (d) Ludwig's angina(Ref. Scott Brown, 8th ed., Vol 3; 550)Ludwig's angina does not involve tonsil. The other options can lead to patch/pseudomembrane on the tonsil.", 'role': 'assistant'}]