Which of the Following Statements About the Length of Television

Which of the following statements about the length of television commercials is true?

A) Commercials have become longer as the demand for broadcast time dwindles.
B) Commercial length is increasing and 60-second spots will become dominant by the end of the decade.
C) Commercials became shorter because advertisers turned to shorter spots as a way of controlling their media costs.
D) Fifteen-second commercials account for over half of the ads seen on network television.
E) The number of 60-second commercials has declined due to a desire by the network to sell more ads and restrict clutter.