How much RMS current does a 300W, 200V bulb take from the 200V, 50HZ power lines ?

How much RMS current does a 300W, 200V bulb take from the 200V, 50HZ power lines ?

A. 0.5A
B. 1.5A
C. 2A
D. 3A

Explanatory answer:

P=V^2/R

Therefore R= V^2/ P

R= 200^2 / 300

R= 133.33 ohm (resistance of lamp)

Rms current 
taken by lamp = rms value of supply voltage /resistance of  lamp

                                         =  200  /  133.33
                                      I   =  1.5A