Correct option is (d) intensities, powers and pressures
Easiest explanation: Decibel expresses the logarithm of the ratio between two sound intensities, powers or sound pressures. The convenient unit for making such comparisons and to express the sound intensity and sound pressure data for all practical purposes is the decibel (dB). The dB is 1/10 of a larger unit, the bell, named after Alexander Graham Bell.
