Look at this famous timothy o'sullivan photo, a harvest of death. why is this photo an important primary source document?
a: it documents early photographic technology.
b: it reveals the devastation of death from war.
c: it shows the landscape of a typical battlefield.
d: it illustrates what kinds of uniforms soldiers wore.

The Timothy O'Sullivan photo, A Harvest of Death, is an important primary source document because it reveals the devastation of death from war (B).
For the purposes of this discussion, a primary source document is an original document that was created at the time of the event it represents. The photo was taken by Timothy O'Sullivan at the Battle of Gettysburg in  1863 and was published in a book called "Photographic Sketch Book of the War" by Alexander Gardner. Alexander Gardner wrote the text which described the photo. 

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