This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose, Subject name: Anatomy
Location Hasner's of valve- 
Select and explain. 
A. Opening of nasolacrimal duct, B. Sphenoidal sinus opening, C. Frontal sinus opening, D. Ethmoidal sinus opening
A: Opening of nasolacrimal duct
Answer: A: Opening of nasolacrimal duct 
Explanation: Ans, is 'a' i.e., Opening of nasolacrimal duct o Nasolacrimal duct opens into inferior meatus and is closed by a mucosal flap called Hasner's valve.