Multiple choice Which of the following sinuses does not open in the middle meatus of nose? Frontal sinus Ethmoidal sinus Sphenoidal sinus Maxillary sinus Reveal answer Fill a bubble to check yourself C Correct answer Explanation Sphenoidal sinus does not open in the middle meatus. The sphenoidal sinus drains into the spheno-ethmoidal recess that is superior to the superior concha.