Which statement is correct about electromagnetic and mechanical waves?

A Electromagnetic waves move much slower than mechanical waves.

B Electromagnetic waves occur when charged particles decelerate, but mechanical waves occur when charged particles accelerate.

C Electromagnetic waves are transverse, but mechanical waves are longitudinal.

D Electromagnetic waves can travel through a vacuum, but mechanical waves need a medium for propagation.

D Electromagnetic waves can travel through a vacuum, but mechanical waves need a medium for propagation.