Final answer:
Lincoln's reference to 'four score and seven years ago' in the Gettysburg Address connects the Civil War to the nation's founding and positions the war as a battle to uphold the ideals of liberty and equality, as intended by the nation's founders.
Step-by-step explanation:
When Abraham Lincoln refers to the time period 'four score and seven years ago' at the beginning of the Gettysburg Address, he is connecting the present struggle of the Civil War to the historical context of the nation's founding. This reference emphasizes that the war is a test of whether the nation, built on principles of liberty and equality, can endure. The correct answer is that Lincoln is presenting the war as a fight to save the legacy of the nation's founders, as he invokes the spirit of the American Revolution and articulates the ideals for which the Union soldiers at Gettysburg fought and died. Thus, the answer to the question is D. He is presenting the war as a fight to save the legacy of the nation's founders.