You are presented with the quiz "What converts electrical energy to sound?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "aradio converts electrical energy into vibrations" and "all sounds are vibrations". So, what's the best answer to the question?

Select from the following. (1). ears; (2). organ; (3). radios; (4). pencils; (5). engines; (6). waves; (7). Gunshots; (8). antennae;
The answer is:
(3).