Opening of the Eustachian tube accomplishes:

• A. It reduces earwax production.
• B. It equalizes pressure in the middle ear, preventing tympanic membrane distortion.
• C. It amplifies sound in the middle ear.
• D. It traps air in the middle ear.

Answer: (B)

Opening the Eustachian tube serves to equalize pressure between the middle ear and the outside environment, so the tympanic membrane remains properly tensioned and can vibrate normally in response to sound. This pressure balance is especially important during altitude changes or when you swallow or yawn, which opens the tube via the muscles of the soft palate. When the pressures are equal, the membrane stays stable and hearing is preserved; when they’re not, the membrane can bulge or be drawn, causing discomfort and muffled hearing. The tube also helps drain middle-ear secretions into the nasopharynx, but its main role related to this question is maintaining pressure balance to prevent tympanic membrane distortion.