system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Eustachian tube opens in?
assistant
The correct answer is  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.