The correct answer is national unity.
This speech was given just one month before the official end of the American Civil War. This war caused significant fighting between the Union and the Confederacy. This war caused the deaths of thousands of American citizens on both sides. As this war was winding down, Lincoln knew that these Confederate States would eventual become part of the US again. To ease this transition, he discusses how the US must "bind up the nation's wounds." When using this phrase, Lincoln is referring to how the Confederate and Union states must work together in order to unite the US once again.
The Kansas-Nebraska Act was passed by the U.S. Congress on May 30, 1854. It allowed people in the territories of Kansas and Nebraska to decide for themselves whether or not to allow slavery within their borders. The Act served to repeal the Missouri Compromise of 1820 which prohibited slavery north of latitude 36°30´.
I believe the answer is B, correct me if I am wrong, but I'm pretty positive that's the answer:)
