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 pure tone audiogram the symbol X is used to mark- 
Select and explain. 
A. Air conduction in right ear, B. Air conduction in left ear, C. Bone conduction in right ear, D. No change in air conduction in right ear
B: Air conduction in left ear
Answer: B: Air conduction in left ear 
Explanation: None