C: the souths focus on growing cash crops led to the development of a slave labor force that was largely unknown north of maryland.
The war changed the economical balance of the world, leaving European countries deep in debt and making the U.S. the leading industrial power and creditor in the world.
The First World War destroyed empires, created numerous new nation-states, encouraged independence movements in Europe’s colonies, forced the United States to become a world power and led directly to Soviet communism and the rise of Hitler. Diplomatic alliances and promises made during the First World War, especially in the Middle East, also came back to haunt Europeans a century later. The balance of power approach to international relations was broken but not shattered. It took the Second World War to bring about sufficient political forces to embark on a revolutionary new approach to inter-state relations.
Hopefully this helps
Pledge of Allegiance contains the phrase "under God" and as such the obligation to participate in the Pledge clashes with the freedom of religion. Freedom of religion is written into law in the First Amendment, adopted in 1791.