What was the significance of the battle at antietam creek?

a. after this battle, mcclellan was promoted by lincoln for pursuing lee’s beaten troops.

b. the bloodiest single-day battle of the war, this attempt of lee's to invade the north was thwarted.

c. this was the site of the first ironclad ship battle.

d. this battle was a turning point of the war, showing britain and france that the confederates had the clear advantage.