What was one result of the growing number of broadcasters and relatively inexpensive radios in the United States during the 1920s?
A. Radio news and music programs became some of the most popular forms of entertainment.
B. Movies became unpopular because people no longer wanted to leave their radios to go to the theaters.
C. High school enrollment decreased because most people felt that listening to the radio was better than reading.
D. Many newspapers and magazines went bankrupt and were replaced by radio as the preferred form of mass media.