Which statement best explains why electromagnetic waves can propagate through empty space whereas sound waves cannot?
(a) Electromagnetic waves push against virtual particles in vacuum, whereas sound cannot do so.
(b) Only transverse waves such as electromagnetic waves can propagate without matter, while longitudinal sound waves always require a material medium.
(c) Oscillating electric and magnetic fields regenerate each other and do not require material particles, while sound needs a medium to transmit pressure disturbances.
(d) Sound waves have much larger wavelengths than electromagnetic waves; such long wavelengths cannot be sustained in empty space.