Why Do Radio Stations Repeat the News So Often Throughout

Why do radio stations repeat the news so often throughout the day?

A) In order for radio news to sink in, people need to hear stories more than once.
B) The audience is constantly changing, because most people listen to the radio in their cars.
C) There is not enough news to fill an entire day's worth of programming.
D) Radio news normally provides more headline than in-depth coverage since it comes directly from the television script.
E) The owners of radio stations are legally allowed to devote only a limited amount of time to political stories.