Respuesta :
The correct answer is: A) the Union's effectiveness at the Batlle of Antietam.
The Emancipation Proclamation was issued on January 1, 1863 by Abraham Lincoln; in it he declared that the people held as slaves within the rebel states or the Confederate States, "are, and henceforward shall be free." Another topic adressed the black military units to establish among the Union Forces. The opportunity to issue the Proclamation came after the Union won at the Battle of Antietam held on September 17, 1862.