question: What is a thin membrane stretched tight across the end of the ear canal that vibrates when sound waves strike it?
distractor3: auricle
distractor1: earlobe
distractor2: cerebrum
correct_answer: eardrum
support: The eardrum is like the head of a drum. It’s a thin membrane stretched tight across the end of the ear canal. The eardrum vibrates when sound waves strike it, and it sends the vibrations on to the middle ear.