Gettysburg Address

which statement BEST explains how Lincoln structure his speech?
a. he opens with a reference to the past, continues by discussing the present, and ends with his hopes for the future
b. he introduces an abstract idea and then provides several specific examples to illustrate that abstract idea
c. he outlines a historical philosophy and contrasts it with a modern approach, allowing the audience to make an informed decision
d. he explains one point of view on a subject, offers a conflicting opinion and finally strongly argues his own point of view