Which of the following frequencies is in the infrasound range?

Infrasound refers to sound waves that are below the audible range of human hearing, typically defined as frequencies lower than 20 Hz. Frequencies in this range can travel long distances and are often associated with natural phenomena such as earthquakes and volcanic activity, as well as man-made sources like machinery and explosions.

In this context, a frequency of 10 Hz falls within the infrasound category. It is below the cutoff frequency of 20 Hz, making it an appropriate example of infrasound.

The other frequencies presented, such as 25 Hz, 10 kHz, and 25 kHz, exceed the infrasound range because they are higher than 20 Hz. The frequencies of 10 kHz and 25 kHz fall well into the audible ultrahigh frequency range, which is widely recognized within human hearing capabilities, particularly for younger individuals. Therefore, the choice of 10 Hz effectively illustrates a frequency that is characteristic of infrasound.