Which of These Statements Describes a Key Difference Between Advertising

Which of these statements describes a key difference between advertising and publicity?

A) Publicity is more expensive on a cost-per-contact basis than advertising.
B) Publicity is easily controlled by the user while advertising is not.
C) Advertising is usually directly paid, and publicity is indirectly paid.
D) Advertising provides an immediate feedback loop, and publicity does not.
E) Publicity results in less credibility with consumers than advertising does.