This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nasal Polyposis, Subject name: ENT
[{'content': 'All of the following are true about antrochoanal polyp except: \nSelect and explain. \nA. Single, B. Unilateral, C. Premalignant, D. Arises from maxillary antrum', 'role': 'user'}, {'content': 'Answer: C \nExplanation: (c) Premalignant(Ref. Scott Brown, 6th ed., 4/10/14)Nasal polyps arise due to edema of the nasal mucosa. They are not premalignant.', 'role': 'assistant'}]