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': 'Nasopharyngeal Ca involve: \nSelect and explain. \nA. Nasal cavity, B. Orophaynx, C. Oral cavity, D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Nasopharyngeal cancer arises from fossa of Rosenmuller in the lateral wall of nasopharynx and can spread to various sites.', 'role': 'assistant'}]