Paul is working on a research paper about the beginning of pop art, a modern-art movement, in the mid-1950s. Paul knows that pop art began in England and became prominent in America in the 1960s. Pop artists used images from popular culture, such as advertisements and news, in their works. Even though Paul has background information about the art movement, he wants to learn more about how pop art began. Which one of the following would be the most credible source for Paul's paper?
A.
a documentary about artistic movements in America from the colonial era to the present
B.
a Web site with a collection of reviews about the different types of modern art
C.
a dated letter written by a famous pop artist explaining his latest artwork
D.
an article written by the director of the pop art exhibit at a prestigious museum
E.
an interview with a frequent visitor at a museum that has a pop art exhibit

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