When a light switch is turned on, the light comes on immediately because
(a) The electrons coming from the power source move through the initially empty wires very fast.
(b) The electrons already in the wire are instantly "pushed" by a voltage difference.
(c) The light-bulb may be old with low resistance. It would take longer if the bulb were new and had high resistance.
(d) The electricity bill is paid. The electric company can make it take longer when the bill is unpaid?