What is the primary function of the middle ear?

The primary function of the middle ear is to amplify sound, which is why amplifying sound is the correct answer. The middle ear contains three small bones called ossicles (the malleus, incus, and stapes), which work together to increase the pressure and strength of sound waves before they reach the inner ear. When sound waves hit the tympanic membrane (eardrum), the ossicles vibrate in response and transmit these vibrations to the oval window of the cochlea, making the sound louder and more discernible to the auditory system.

Regulating balance is the role of the inner ear, specifically the vestibular system, rather than the middle ear. Transmitting electrical signals to the brain occurs in the inner ear, particularly in the cochlea, where sensory hair cells convert mechanical vibrations from sound into electrical impulses. Filtering out background noise is not a primary function of the middle ear, although the auditory system does have mechanisms for distinguishing between different sound frequencies; this function is primarily related to how the brain processes auditory information rather than the middle ear's role.