This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
Which is not a content of tympanic cavity : 
Select and explain. 
A. Maleus, B. Chorda tympani, C. Stapedius, D. Post. auricular N
D: Post. auricular N
Answer: D: Post. auricular N 
Explanation: Contents of middle ear or tympanic cavity are auditory ossicles (malleus, incus, and stapes), stapedius & tensor tympani muscles, chorda tympani nerve0 (a branch of 70 cranial nerve) and tympanic plexus of nerves.