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
On otological examination all of the following with have positive fistula test except - 
Select and explain. 
A. Dead ear, B. Labyrinthine fistula, C. Hypermobile stapes footplate, D. Following fenestration surgery
A: Dead ear
Answer: A: Dead ear 
Explanation: None