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: Social & Preventive Medicine
Auditory fatigue occurs at ? 
Select and explain. 
A. 50 dB, B. 60 dB, C. 80 dB, D. 90 dB
D: 90 dB
Answer: D: 90 dB 
Explanation: Ans. is 'd' i.e., 90 dB Auditory effects of noice A uditoryfatigue- 90 dB and 4000 Hz. Deafness Temporary - 4000 to 6000 Hz Repeated prolonged exposure to 100 dB Permanent Single exposure to 160 dB (due to rupture of ear drum)