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
[{'content': 'Which is not a content of tympanic cavity : \nSelect and explain. \nA. Maleus, B. Chorda tympani, C. Stapedius, D. Post. auricular N', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 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.', 'role': 'assistant'}]