Paranasal sinuses present at bih ?: (A) Frontal and maxillary, (B) Ethmoid and maxillary, (C) Frontal and ethmoid, (D) Sphenoid and ethmoid
Answer is B. Ans. is 'b' i.e., Ethmoid and maxillary Maxillary sinus - 4 Develop at bih; completely develop at 9 years Ethmoidal sinus - Develop at bih; completely develop at late pubey Frontal sinus - Develop at 2 year; completely develop at late adolescence Spenoid sinus - Develop at 3-5 years; completely develop at 12-15 years