The mechanism of heat transfer in the atmosphere is convection. Which statement is true about convection?

AConvection occurs in all forms of material.

BConvection is the transfer of heat energy through a vacuum or any transparent media in the form of electromagnetic waves.

CConvection is the transfer of heat energy through a substance without the substance moving.

DConvection is the transfer of heat energy from one place to another by the movement of the substance itself.