Answer:
(D) The signing of the emancipation proclamation described the secondary source about the Gettysburg address “set the precedent that the states would ultimately remain indivisible as members of single nation”.
Step-by-step explanation:
This is because this is one of the major and the significant things which is stated in the flag and must be rendered by all human beings in the country. Members of the armed forces are also involved in the same and thus the manner in which the speech is given also holds some importance.