The marking “60 W – 230 V” is printed on an incandescent lamp. What does this marking indicate?
(a) The lamp draws a current of 60A when connected to a 230V supply.
(b) The lamp converts electrical energy at 60J s−1 when connected to 230V.
(c) The filament resistance is 60Ω at its rated voltage of 230V.
(d) The lamp converts 60J of electrical energy in 230s irrespective of the supply voltage.