This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Congenital Lesions and Stridor, Subject name: ENT
Sphenoidal sinus opens into: 
Select and explain. 
A. Superior meatus, B. Inferior meatus, C. Middle meatus, D. Spheno-ethmoidal recess
D: Spheno-ethmoidal recess
Answer: D: Spheno-ethmoidal recess 
Explanation: (d) Spheno-ethmoidal recess(Ref. Cummings, 6th ed., 659)The Sphenoid sinus opens into the spheno-ethmoidal recess just above the superior turbinate.