Discomfort due to sound usually begins around:
Pick C: 120 dB. Thinking about Sensory System Ear Physiology in a practical way — what the structure does, or what the process achieves — leads you here. Clinically and academically, the same logic shows up again and again: cause and effect line up with 120 dB — that is the mechanism or reason the stem is pointing to. Hence 120 dB is correct. Treat this as a building block for the rest of Sensory System Ear Physiology; neighbouring topics often reuse the same principle. Keep a one-line summary card for this idea and revisit it before the paper; short, repeated review beats long cramming sessions.
Ref: Animal physiology is Unit 7 of the CSIR NET Life Science Syllabus, covering core body systems. It accounts for roughly 10% of the total marks in Sections B and C.