The author thinks of advertisements as ______.

A．There is no popularity that really counts.
B．What many parents are doing is in fact hindering their children from finding their own paths.
C．It is not necessarily bad for a teenager to disagree with his or her classmates.
D．Most teenagers claim that they want to do what they like to, but they are actually doing the same.

A．"sell" his or her ideas to an audience
B．maintain direct eye contact with listeners
C．be very persuasive and believable
D．be exceptionally well-disposed