Some animals make sounds that humans cannot hear. Some of these sounds fall below the frequency threshold for human hearing, i.e., at frequencies less than about 20 Hz. These are usually described as
A) infrasound.
B) substrate vibration.
C) "tings."
D) ultrasound.

Question

Quizplus · Accepted Answer

Infrasound refers to sound waves that are below the frequency threshold of human hearing, which is less than about 20 Hz. These low-frequency sounds can be produced by various natural phenomena and some animals.

Some Animals Make Sounds That Humans Cannot Hear