This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oral cavity & Oesophagus, Subject name: ENT
[{'content': 'All are precancerous lesions of oral cavity except \nSelect and explain. \nA. Leukoplakia, B. Erythroplakia, C. Diffuse oral submucous fibrosis, D. Diffuse aphthous ulcers', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Premalignant Lesions - Leukoplakia Erythroplakia Oral submucous fibrosis Melanosis and mucosal hyperpigmentation Ref: Dhingra; Textbook of Ear, Nose and Throat; 7th Edition; Page 253', 'role': 'assistant'}]