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: Dental
Gold Standard for evaluation of any obstruction in the nasal pathway: 
Select and explain. 
A. Mirror test., B. Butterfly test., C. Rhinomanometry., D. To check the size of nostril.
C: Rhinomanometry.
Answer: C: Rhinomanometry. 
Explanation: None