This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
[{'content': 'Eustachian tube opens in? \nSelect and explain. \nA. Inner ear, B. Middle ear, C. Outer ear, D. Larynx', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Middle ear * Eustachian tube (pharyngotympanic tube) is a channel connecting the tympanic cavity (middle ear cavity) with nasopharynx. Therefore, ear infection can travel to throat through eustachian tube and vice-versa.* Eustachion tube opens into anterior wall (carotid wall) of medial ear.", 'role': 'assistant'}]