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
The maxillary sinus opens into middle meatus at the level of - 
Select and explain. 
A. Hiatus semilunaris, B. Bulla ethmoides, C. Infundibulum, D. None of the above
A: Hiatus semilunaris
Answer: A: Hiatus semilunaris 
Explanation: None