Which of the following is NOT an ossicle of the middle ear:

A. pinna

B. stapes

C. incus

D. malleus

A. pinna

Explanation:

The middle ear is very narrow measuring less than 10 millimeters in diameter but is widened by small muscles. In this region the tympanum vibrates through sound waves that enter the middle ear through its three ossicles which are stapes, incus and malleus. The pinna is part of the outer ear, literally the part of the ear that everyone can see.