The correct answer is 75 decibel.As per the Noise Pollution Rules 2000, the permissible limits of noise pollution in residential areas are 55 dB and 45 dB during the day and night respectively.For the silence zones, the prescribed limit is 50 dB during the day and 40 dB during the night.For the industrial areas, the permissible limit of noise pollution is 75 dB during the day and 70 dB during the night.For the commercial areas, 65 dB is permitted during the day and 55 dB is permitted during the night.Hence, the correct answer is 75 dB. Additional InformationA decibel meter is a measuring instrument used to assess noise or sound levels by measuring sound pressure.Often referred to as a sound pressure level (SPL) meter, decibel (dB) meter, noise meter, or noise dosimeter, a sound level meter uses a microphone to capture sound.We measure sound intensity (also referred to as sound power or sound pressure) in units called decibels.Decibels (dB) are named in honour of Alexander Graham Bell.He was the inventor of both the telephone and the audiometer.