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: 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: Lesions with an increased risk of malignancy\n\nPremalignant condition : - Leukoplakia, Erythroplakia, Speckled erythroplakia, chronic hyperplastic, candidiasis.\nConditions increasing risk : - Oral submucous fibrosis, syphilitic glossitis, sideropenic dysphagia (Paterson Kelly syndrome).\nThe risk is doubtful: - Oral lichen planus, DLE, Dyskeratosis congenita.', 'role': 'assistant'}]