This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
[{'content': 'Auditory fatigue occurs at ----Hz- \nSelect and explain. \nA. 2000, B. 3000, C. 4000, D. 8000', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Auditory fatigue appears in the region of 90dB and greatest at 4000 Hz. It may be associated with side effects such as whistling and buzzing in the ears. Temporary hearing loss at 4000-6000 Hz. (PARK TB 23rd edition pg 742)', 'role': 'assistant'}]