Which of the following is a TRUE statement about the differences between electromagnetic and mechanical waves?

A
Electromagnetic waves are caused by vibration of particles and mechanical waves are caused by frequency, not amplitude.

B
Electromagnetic waves are considered a periodic disturbance and mechanical waves are considered a disturbance.

C
Electromagnetic waves require a medium to travel in and mechanical waves do not require a medium.

D
Electromagnetic waves travel in a vacuum and mechanical waves do not travel in a vacuum.