Which of the following frequencies is outside the audible range for humans?

The correct answer is that 5 Hz is outside the audible range for humans. The human audible range typically spans from approximately 20 Hz to 20 kHz. Frequencies below 20 Hz are considered infrasonic, which means they are too low for most humans to hear.

In contrast, frequencies such as 15 kHz, 500 Hz, and 1 kHz fall within the audible range. Specifically, 15 kHz is on the upper end of this range, while 500 Hz and 1 kHz are well within the middle range. Understanding the characteristics of different frequency ranges helps in various applications, including audio engineering, sonography, and understanding sound perception.