Which statement accurately describes the Battle of Antietam?

A.
It produced relatively light casualties compared to other battles.

B.
It was a decisive victory for the Confederates, who then invaded Pennsylvania.

C.
It convinced President Abraham Lincoln that General George B. McClellan was the general who could win the war.

D.
It gave President Abraham Lincoln justification to issue the Emancipation Proclamation.
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As you can see I suck at History....Help please?