A 30 dB increase in noise pollution level represents

AA 30-fold increase in sound intensity

BA 100-fold increase in sound intensity

CA 1000-fold increase in sound intensity ✓ Correct

DA 15-fold increase in sound intensity

Correct answer: (C) A 1000-fold increase in sound intensity

Explanation

A rise of 30 decibels means sound intensity grows a thousand times.

A 30 fold increase does not match, since decibels use a logarithmic, not a linear, scale.

A 100 fold increase corresponds to a 20 decibel rise, not 30.

A 15 fold increase has no simple decibel equivalent and is incorrect here.

Every 10 decibel step multiplies intensity by ten, so three steps give ten cubed.

The decibel scale compresses a vast range of intensities into manageable numbers.

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