Which choice describes a claim Lincoln makes in the “Gettysburg Address”?

a) The citizens have a duty to save the nation since soldiers gave their lives to preserve the union of states.

b) The southern states must surrender because all states agreed to be governed by the U.S. Constitution.

c) The democratic government will be replaced if war breaks the United States into two separate nations.

d) The northern states and southern states must look beyond their differences and create a peace agreement.