Brandon is writing a research paper on this topic: changes in the game of football in the twentieth century. He needs to use a secondary source. Which source should he choose?
A.
a photograph of a football player taken in 1948
B.
a player’s account of what it was like to play in the National Football League
C.
a biography about quarterback Joe Namath
D.
a piece of video footage of the 1979 Super Bowl