What happens when you call someone using your cell phone?
A. Microwaves travel from your cell phone directly to the cell phone
of the person you are calling.
B. Microwaves reach a cell tower, then fiber optic cables send the
signal to a cell tower near the person you are calling.
C. A system of satellites orbiting Earth receives the microwave
signals and sends them to the person you are calling.
D. Sound waves reach a cell tower, then fiber optic cables send the
signal to a cell tower near the person you are calling.