The Union was more welcome to the immigrants because they weren't enslaving people. The south had a steady group of people coming in, just for slavery.
(B) The Union blockade kept many from arriving there.
Explanation: this makes more sense because during the civil war the union blockade prevented southern states from trading, also the union blockade prevented troops and weapons from entering the southern states, by doing this the Union thought they could cause the economy of the confederate states to collapse.
Alexander Hamilton and Thomas Jefferson disagreed over the proposed "National Bank" based on which issue? whether or not the Constitution gives the national government the power to establish the bank.