Pressure in the middle ear is equalized through which part of the body?

• A. Eustachian tube
• B. Auditory canal
• C. Tympanic membrane
• D. Nasal cavity

Answer: (A)

Pressure in the middle ear is equalized through the Eustachian tube, a passage connecting the middle ear to the upper throat (nasopharynx). It normally stays closed, but swallowing or yawning opens it, allowing air to move in or out so the middle-ear pressure matches the outside environment. This prevents discomfort or injury during altitude or depth changes. The other structures aren’t the route for pressure equalization: the auditory canal is the external ear canal, the tympanic membrane is the eardrum, and the nasal cavity is part of the nose, not the pressure-equalizing pathway.