ANSWER:
Actually the only correct answer is B. Make sure that the power is switched off and the power cord is unplugged.
B is the obvious answer but the reason why the other ones are wrong is CRT monitors can hold over 20,000 volts of electricity. Even when they are unplugged and turned off. Grounding yourself to 20,000 volts would not be a smart choice as you may end up a burnt spot on the floor.