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': 'The most common pre-malignant condition of oral carcinoma is - \nSelect and explain. \nA. Leukoplakia, B. Erythroplakia, C. Lichen planus, D. Fibrosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Two important premalignant lesions for oral cancer are : -\n\n\nLeukoplakia\nErythroplakia\n\n\nLeukoplakia is the most common premalignant lesions.\nBut, the risk of malignant transformation of erythroplakia is much higher than that seen with leukoplakia.\nThe most common predisposing factor for both these conditions is smoking.', 'role': 'assistant'}]