What is the function of the cochlea in the inner ear?

The cochlea plays a critical role in the auditory system by converting sound vibrations into neural signals that can be interpreted by the brain. Located in the inner ear, it is a spiral-shaped, fluid-filled structure that contains hair cells, which are sensory receptors. When sound waves enter the ear, they cause vibrations in the fluid within the cochlea. These vibrations create waves that move the hair cells, leading to the generation of electrical signals. These signals are then transmitted through the auditory nerve to the brain, where they are processed and recognized as sound.

While collecting sound waves is the primary function of the outer ear, maintaining balance is mainly managed by the vestibular system, and regulating air pressure is the function of the Eustachian tube, which connects the middle ear to the throat. Therefore, the cochlea's unique and essential function is in the transmission of sound vibrations, making this option the best choice.