When you are channel-surfing one evening, you come across an infomercial for the Ronco Indoor Rotisserie, and the hosts show you how to cook chicken, beef, pork and even hot dogs with ease. Additionally, if you call the toll-free number during the show, you will get a Ronco Chop-O-Matic for free. The infomercial is an example of:

a) public relations.

b) direct marketing.

c) publicity.

d) personal selling.

e) advertising.