This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
Maxillary sinus achieves maximum size at 
Select and explain. 
A. bih, B. Primary dentition, C. At secondary dentition, D. At pubey
C: At secondary dentition
Answer: C: At secondary dentition 
Explanation: Maxillary sinus is the first sinus to develop at bih. It is completely developed by 9 years of agei.e approximately at secondary dentition Ref Maqbool 11/e,p148.