Gulf war was taken action on 1991
It is B, the entire point of the removal act was a land trade.
An unequal distribution of resources.
It's C
The north had the money, the people, and the industrial power to branch out the railroad networks. So following markets and money. The north built networks to the west.
The south in contrast was did not have the capacity to construct as much railroads as the north did so therefore there was less western expansion. As well the south had more interests building canals and shipping product of the states to England.