Question

which structure helps to equalize air pressure on both sides of the tympanic membrane? oval window external acoustic meatus semicircular canals auditory tube

Explanation:

The auditory tube (Eustachian tube) connects the middle - ear to the nasopharynx and helps equalize air pressure on both sides of the tympanic membrane. The oval window transmits sound vibrations from the middle ear to the inner ear. The external acoustic meatus is the ear canal that leads to the tympanic membrane. The semicircular canals are part of the inner - ear and are involved in balance, not pressure equalization.

Answer:

D. Auditory tube