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
Eustachian tube function is best assessed by: 
Select and explain. 
A. Tympanometry, B. VEMP, C. Rhinomanometry, D. Politzer test
A: Tympanometry
Answer: A: Tympanometry 
Explanation: Ans: A. Tympanometry(Ref Dhingra 7/e p62-63, 6/e p59)Assessment of eustachian tube function:Tympanometry & Politzer test.Tympanometry better than Politzer test.Tympanometry:Positive & negative pressures created in external ear canal.Patient swallows repeatedly.Normal tubal function:Ability of tube to equilibrate positive & negative pressures to ambient pressure.Done both in patients with perforated or intact tympanic membrane.