Answer
(d) 16
Work Step by Step
According to Stefan's law the total intensity of the emitted radiation from thermal objects (blackbody radiator) is proportional to the fourth power of the absolute kelvin temperature ( $T^{4}$ ) of the object.
So if the absolute temperature of a blackbody radiator is doubled the total energy emitted will be proportional to $(2T)^{4}$ . Thus a increase by a factor of $(2)^{4}$= 16.
