What is the frequency range to which a normal ear can respond, measured in Hertz?

A normal human ear can typically respond to a frequency range from approximately 20 Hz to 20,000 Hz (20 kHz). This range includes the low frequencies, which are important for perceiving bass sounds, and the high frequencies, which are crucial for understanding speech and detecting sounds in the environment.

The lower limit of 20 Hz corresponds to the threshold of hearing for most individuals, while the upper limit of 20,000 Hz represents the maximum frequency that can normally be heard by young, healthy humans. As people age or if they have certain auditory conditions, the ability to hear higher frequencies may diminish.

The other frequency ranges provided do not accurately reflect the normal auditory capabilities of the human ear. For instance, the option stating 20-18,000 Hz does not encompass the full range as it stops short of the upper limit of 20 kHz. Similarly, the ranges of 20-15,000 Hz and 20-25,000 Hz also do not correctly indicate the typical frequency range of human hearing. Thus, the correct answer reflects the most widely accepted range for normal hearing sensitivity.