This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
Most commonly used tuning fork in ear examination- 
Select and explain. 
A. 128 Hz, B. 256 Hz, C. 512 Hz, D. 1024 Hz
C: 512 Hz
Answer: C: 512 Hz 
Explanation: Ans. is 'c' i.e., 512 Hz o Commonly used tuning fork has a frequency of 512 Hz-o Forks of other frequencies, e.g. 256 and 1024 Hz should also be available.