The Seller (Or the Writer)of a Call Option

The seller (or the writer) of a call option:

A) has the right to buy the underlying asset at a strike price until an expiration date
B) has the right to sell the underlying asset at a strike price until an expiration date
C) may have the obligation to buy the underlying asset at a strike price until an expiration date
D) may have the obligation to sell the underlying asset at a strike price until an expiration date
E) None of these answers are correct.