Alexander Hamilton wrote the majority of the Federalist Papers.
The Americans won the Spanish-American War. As a result of the Treaty of Paris, the US gained territory in the Pacific and Carribean, including Guam, Puerto Rico, and the Philippines. This led to the US increasing production of more foreign goods that they could now produce in their own territories, and therefore expanded their markets.
The Northern states enjoyed increasing political representation and power born from rapid population growth. Because of the South’s investment in agriculture any attack on slavery, which was witnessed in the North, was an attack on Southern economy itself. Webster viewed slavery as a matter of historical reality rather than moral principle. Congress had prohibited slavery in the Northwest Ordinance of 1787 and divided regions into slave and free in the 1820 Missouri Compromise. Slavery where it existed could not be eradicated but it could not also take root in the newly acquired agriculturally barren lands on the southwest.
Improved income and mobility resulted in many things, and most of these answers are related to one another, but the best single option would be "<span>c. the development of suburbs."</span>
