Final answer:
The ear determines the origin of a sound by amplifying sound waves via the middle ear bones, which then transmit to the cochlea. These are translated into neural signals and carried to the brain, which interprets differences between ears to locate sound sources.
Step-by-step explanation:
The structure of the ear allows a person to determine the origin of a sound through a process involving several components. Sound waves enter through the outer ear and cause the eardrum to vibrate. These vibrations are then amplified by the three small bones in the middle ear: the malleus, incus, and stapes (hammer, anvil, and stirrup). The amplified vibrations are transmitted to the inner ear via the oval window. Within the cochlea, fluid movements stimulate tiny hair cells that convert vibrations into neural signals. The auditory nerve carries these signals to the brain. The brain interprets slight time differences and intensity disparities between both ears to pinpoint the location of the sound source, with the correct answer to the student's multiple choice question being option d). The outer ear, including the pinna and auditory canal, helps to focus sound waves, the middle ear amplifies them, and the inner ear, featuring the cochlea, transduces them into a neural signal.