(A) stopped
(B) impeded
(C) blocked
(D) ** propelled
EXPLANATIONS BELOW
Concept note-1: -Union Claims Victory Military historians consider the Battle of Antietam a stalemate. Even so, the Union claimed victory. And keeping Confederates in their southern box enabled President Lincoln to finally release his Emancipation Proclamation on September 22, 1862.
Concept note-2: -The Emancipation Proclamation issued soon after the battle of Antietam was not without precedent. The Lincoln administration declared slavery illegal in the territories on 19 June 1862.
Concept note-3: -Most importantly, Union victory at Antietam provided President Abraham Lincoln the opportunity he had wanted to announce the Emancipation Proclamation, making the Battle of Antietam one of the key turning points of the American Civil War.
Concept note-4: -Antietam, the deadliest one-day battle in American military history, showed that the Union could stand against the Confederate army in the Eastern theater. It also gave President Abraham Lincoln the confidence to issue the preliminary Emancipation Proclamation at a moment of strength rather than desperation.