When sound waves travelling through the air reach the human

ear, the cochlea (read as: KOE-klee-ah) converts the sound wave into:

W) A chemical response transmitted through the blood stream

X) An electrical impulse sent to the brain

Y) A lower frequency wave, which resonates within the ear

Z) Many small wave vectors that are separately communicated to the brain
X) AN ELECTRICAL IMPULSE SENT TO THE BRAIN