For the first question, the best name for the map would be: D "US Expansion Before the Civil War". This title accurately reflects the historical context of U.S. territorial expansion leading up to the Civil War.
For the second question, the correct match of a current state with the area labeled on the map is: B Arizona: Mexican Cession. The Mexican Cession refers to territories ceded to the U.S. after the Mexican-American War, which includes present-day Arizona.