This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oral Cavity, Subject name: ENT
[{'content': 'All of the following lesions of the oral cavity are premalignant except- \nSelect and explain. \nA. Erythroplakia, B. Hyperplastic candidiasis, C. Sideropenia, D. Aphthous ulcer', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Aphthous ulcer Lesions with increased risk of malignancy* Premalignant condition: - Leukoplakia, Erythroplakia, Speckled erythroplakia, chronic hyperplastic candidiasis.* Conditions increasing risk: - Oral submucous fibrosis, syphilitic glossitis, sideropenic dysphagia (Peterson Kelly syndrome).* Risk is doubtful: - Oral lichen planus, DLE, Dyskeratosis congenita.* Not premalignant:- Aphthous ulcers.", 'role': 'assistant'}]