Power: the Voltage and Power Ratings of a Particular Light

Multiple Choice

Power: The voltage and power ratings of a particular light bulb, which are its normal operating values, are 110 V and 60 W. Assume the resistance of the filament of the bulb is constant and is independent of operating conditions. If the light bulb is operated at a reduced voltage and the power drawn by the bulb is 36 W, what is the operating voltage of the bulb?

A) 66 V
B) 72 V
C) 78 V
D) 85 V
E) 90 V