Final answer:
One decibel is defined as ten times the logarithm to base 10 of the ratio of the intensity of the sound to an arbitrary reference sound intensity, which is true. The unit decibel is named after Alexander Graham Bell.
Step-by-step explanation:
One decibel is indeed defined as ten times the logarithm to base 10 of the ratio of the intensity of a sound to a reference sound intensity. This ratio is unit-less, and the unit decibel (dB) indicates this ratio is multiplied by 10. Therefore, statement B from the options given, which describes decibels as being ten times the logarithm to base 10 of the ratio of two sound intensities, is true.
The decibel is named after Alexander Graham Bell, and the term "deci" means "one-tenth", reinforcing that a decibel is one-tenth of a bel. Sound intensity level, expressed in decibels, is a relative measure compared to a reference intensity, which is commonly 10⁻¹² W/m², the threshold of hearing for a person with normal hearing at a frequency of 1000 Hz. Moreover, our perception of sound is logarithmic, which is why the decibel scale is useful for expressing sound intensity levels.