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
In Bing test, on alternately compressing and releasing the external acoustic meatus, the sound increases and decreases. What does this indicate? 
Select and explain. 
A. Otosclerosis, B. Sensorineural deafness, C. Adhesive otitis media, D. Chronic suppurative otitis media
B: Sensorineural deafness
Answer: B: Sensorineural deafness 
Explanation: Bing test It is a test of bone conduction which examines the effect of occlusion of the ear canal and the hearing. A vibrating tuning fork is placed on the mastoid while the examiner alternately closes and opens the ear canal by pressing on the tragus inwards. A normal person / one with sensorineural hearing loss hears louder when ear canal is occluded and softer when the canal is open. A patient with conductive hearing loss will appreciate no change.