Answer:
Thomas of Illinois then added an amendment that allowed Missouri to become a slave state but banned slavery in the rest of the Louisiana Purchase north of latitude 36°30′.
It would be D because during the civil war Maryland was a border state between the confederacy and Union. Maryland was also a slave holder state which meant it could secede easily. It would also make it vulnerable to the union if it seceded but both ways too.
<span>They became League of Nations mandates</span>
I think the answer is B .... :)