The correct answer is: B. infrasonic
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.
The frequency of a sound wave is the number of times the wave vibrates in one second. The unit of frequency is the hertz (Hz). Human hearing can typically detect sounds with frequencies between 20 Hz and 20,000 Hz.
Sounds with frequencies below 20 Hz are called infrasonic sounds. Infrasonic sounds are too low in frequency for humans to hear, but they can be detected by some animals, such as elephants and whales. Infrasonic sounds can travel long distances through the air and through the ground. They can also be used to create vibrations that can be felt by humans.
Sounds with frequencies above 20,000 Hz are called ultrasonic sounds. Ultrasonic sounds are too high in frequency for humans to hear, but they can be detected by some animals, such as bats and dolphins. Ultrasonic sounds can be used to create images of objects, to clean surfaces, and to kill bacteria.
Supersonic sounds are sounds with frequencies above the speed of sound. The speed of sound in air is about 343 meters per second. Supersonic sounds can be created by aircraft, rockets, and explosions. Supersonic sounds can cause a sonic boom, which is a loud noise that is caused by the sudden change in pressure that occurs when a supersonic object travels through the air.