The frequency range of human hearing is:

The frequency range of human hearing is indeed 20 to 20,000 Hz. This range represents the limits of sound frequency that the average human ear can detect, spanning from low-frequency sounds, such as deep bass notes, to high-frequency sounds, like those produced by a whistle. This range is essential for understanding how hearing aids function, as they must amplify sounds within this spectrum to be effective for users with hearing loss.

The other options do not accurately describe the frequency range of human hearing. The first option mistakenly states a range in decibels, which measures sound intensity rather than frequency. The second option incorrectly uses decibels again when describing the frequency range, leading to confusion. The last option references the place theory of hearing, which explains how different parts of the cochlea respond to different frequencies, but it doesn’t define the frequency range itself. Thus, the correct answer clearly identifies the acceptable frequency range for human hearing.