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: ENT
Facial recess or the posterior sinus is bounded by - 
Select and explain. 
A. Medially by the vertical part of VII nerve, B. Laterally by the chorda tympani, C. Above by the fossa incudis, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Facial recess or Posterior sinus – It is a depression in the posterior wall of the middle ear.
It is bounded by:
Medially – Vertical part of VIII nerve
Laterally – Chorda tympani
Above – Fossa incudis
Importance – This recess is important surgically, as direct access can be made through this into the middle ear without disturbing posterior canal wall. (Posterior tympanotomy approach)