A, the sound of drum music is produced by the vibration of the drum surface. The vibration of the drum surface causes the vibration of the air outside the drum, and then transmits the vibration to the human ear, not through the vibration of the air inside the drum. So, A is wrong;
B, drum music is produced by drum surface vibration, so B is correct;
C, drum music is introduced into people's ears through the air, so C is correct;
D, sound propagation needs medium, and drum music can't spread directly in a vacuum, so D is correct.
So choose a.