A. Audiosonic
B. Infrasonic
C. Ultrasonic
D. Supersonic
Submitted by: Fahad Mehsud
Sounds with frequencies below 20 hertz are called infrasound. Infrasound is too low-pitched for humans to hear. Sounds with frequencies above 20,000 hertz are called ultrasound.
Correct Answer: Infrasonic ✔
Last Updated: May 21, 2020