Why was antietam a major turning point in the civil war?
a. it was the last time confederate troops would enter union territory
b. the close victory afforded president lincoln the opportunity to announce
emancipation
c. robert e. lee lost his aggressiveness for the rest of the campaign in virginia
d. confederate forces were forced to hurriedly withdraw into the carolinas

The answer is B. The close victory afforded President Lincoln the opportunity to announce  emancipation.

The battle at Antietam ended with 23,000 men killed, wounded, or listed as missing. It is the single bloodiest day in the history of the United States. President Abraham Lincoln would later announce the Emancipation Proclamation due to their victory.

I hope this helps! :)

bismarck believed in using force

is the correct answer!