This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
Which of the following is NOT a content of medial wall of middle ear: 
Select and explain. 
A. Oval window, B. Round window, C. Processus cochleariformis, D. Aditus ad antrum
D: Aditus ad antrum
Answer: D: Aditus ad antrum 
Explanation: Ans. (d) Aditus ad antrumReft Dhingra's ENT 6th edj 5-6* Aditus ad antrum is located on posterior wall. It is a doorway to antrum of mastoid.* Antrum is largest mastoid air cell.