Fact 1: Aradio converts electrical energy into vibrations. Fact 2: Electric energy is stored in batteries. Given the two facts above, what does a radio use to make vibrations?

Pick from:
[a]. waves.
[b]. rays or beams.
[c]. a battery.
[d]. an object.
[e]. barrel-shaped.
[f]. nerves.
[g]. Loud noises.
[h]. it needs them.
The answer is:
[c].