This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2017, Subject name: ENT
Which of the following sinus grows till early adulthood:- 
Select and explain. 
A. Maxillary, B. Ethmoidal, C. Frontal, D. Sphenoid
C: Frontal
Answer: C: Frontal 
Explanation: Development of paranasal sinuses Sinus Present at bih 1st X-Ray appearance, Adult size Maxillary Yes 4-5 months after bih 15-18 yrs. Ethmoid Yes 1yr 12yr Sphenoid Yes 6-7yr 15yr Frontal No 4-5yr 18yr