A、Associated Press and United Press International. B、AFP and United Press International. C、Associated Press and Reuters. D、AFP a

The history of American newspapers has paralleled the history of our culture. As our society has changed, so have its newspapers.
    Early colonial newspapers were designed for the elite—those who were interested in political and business information. With the advent of new technology, compulsory education and the major cultural changes brought on by industrialization and urbanization, newspapers moved into the popular culture with the advent of the penny press.
    The significant changes in our society as the United States was transformed into a truly industrial nation between the end of the Civil War and the turn of the 20th century brought about many changes in American journalism, including the era of sensationalism, or yellow journalism.
    Twentieth-century newspapers, for the most part, have attempted to blend objectivity and social responsibility. This era also has seen the development of electronic news media, interpretative  reporting, investigative reporting, advocacy journalism, "new journalism" and specialized newspapers.
    Wire services play an important role in gathering news and information for the mass media. The two largest American wire services are the Associated Press and United Press International. The other dominant worldwide news sources are AFP, Reuters and Tass, headquartered in Paris, London and Moscow, respectively.
    Individual biases and other problems play a role in making mass communication a complex  activity. Although the various functions of the media—to inform, entertain, influence, advertise and transmit culture—are criticized, the most severely criticized is the function to inform. Reasons for this are that people (1) tend to blame the messenger for unpleasant information, (2) fail to understand the watchdog function of the media, (3) believe the myth that the mass media dwell only on bad news and (4) bring their own biases into the information-sharing process.