allerySound levels above 80 dB sustained for long periods can:
AHave no effect
BCause hearing damage and various health problems
CIncrease concentration
DBoost immunity
Answer & Solution
Correct answer: B. Cause hearing damage and various health problems
Above 80 dB sustained, sound becomes physically painful and prolonged exposure damages hearing irreversibly — eardrum injury, cochlear hair cell death.
**Also:** stress, raised blood pressure, sleep disruption.
WHO recommends staying under 70 dB averaged over 24 hours.
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