Which example BEST illustrates a primary research source?
A
a historical analysis of life on the prairie during the 1800s

B
the diary of a woman crossing the prairie in a covered wagon during the 1800s

C
a novel that tells the story of one pioneer family's struggles crossing the prairie during the 1800s

D
a documentary about the effects of the westward movement and homesteading on the prairie during the 1800s