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
Through which of the following pas of nasal cavity does the main current of airflow occur during inspiration? 
Select and explain. 
A. Through olfactory area, B. Superior pa of the cavity in the superior meatus, C. Middle pa of the cavity in middle meatus in a parabolic curve, D. Lower pa of the cavity in the inferior meatus in a parabolic curve
C: Middle pa of the cavity in middle meatus in a parabolic curve
Answer: C: Middle pa of the cavity in middle meatus in a parabolic curve 
Explanation: Airflow through the nose is a result of pressure difference created by a negative pressure gradient generated by the expanding intrathoracic volume during inspiration. Majority of air flows through the middle meatus of the nasal cavity and takes a parabolic curve, as the airflow curves inferiorly as it passes through the choanae into the nasopharynx.