This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: NEET 2018, Subject name: ENT
[{'content': "Nasopharyngeal chordoma arises from:- \nSelect and explain. \nA. Pharyngeal bursa, B. Notochord, C. Rathke's pouch, D. Luschka's bursa", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Nasopharyngeal chordoma Rare type of malignant neoplasm from remnants of the notochord Approximately one-third of chordomas are located in the base of the skull, in the midline of the body. Slow growth rate of the tumor, which gradually fills the nasopharyngeal cavity leads to delayed oncological diagnosis. Obstruction of the nasopharynx is dominant, sleep-disordered breathing (SDB) may occur.', 'role': 'assistant'}]