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': 'Which of the following is precancerous lesion? \nSelect and explain. \nA. Pachydermia of larynx, B. Laryngitis sicca, C. Keratosis of larynx, D. Scleroma larynx', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Keratosis of larynx/leukoplakia:? It is epithelial hyperplasia of the upper surface of one or both vocal cords. Appears as a white plaque or way growth on cord without affecting its mobility Regarded as a precarcerous condition as Ca in situ develops frequently T/t=stripping of cords', 'role': 'assistant'}]