There's a Call Option Written for 100 Shares of GM

Multiple Choice

There's a call option written for 100 shares of GM stock for $85.00 a share, prior to the third Friday of October 2017: The option writer:

A) has the requirement to sell 100 shares of GM for $85 a share on or before the third Friday of October 2017 if the option holder wants to exercise the option.
B) has the option to sell 100 shares of GM for $85 a share on or before the third Friday of October 2017.
C) can cancel the option before the third Friday of October 2017.
D) does not have to post margin while the option holder does.