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 nasopharynx is lined by which epithelium \nSelect and explain. \nA. Stratified squamous non-keratinized, B. Ciliated columnar, C. Stratified squamous keratinized, D. Cuboidal', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The pharyngeal wall consists of 4 layers from within outwards \n1. Mucous membrane: Epithelium is ciliated columnar in the nasopharynx and stratified squamous elsewhere.\n2. Pharyngeal aponeurosis (pharyngobasilar fascia).\n3. Muscular coat: 2 layers\nExternal layer :\n- superior, middle, and inferior constrictors.\n\u200b\u200bInternal layer :\n- stylopharyngeus, salpingopharyngeus\xa0and palatopharyngeus muscle.\n4. Buccopharyngeal fascia.', 'role': 'assistant'}]