The history of the United States from 1865 until 1918 covers the Reconstruction Era, the Gilded Age, and the Progressive Era, and includes the rise of industrialization and the resulting surge of immigration in the United States. This article focuses on political, economic and diplomatic history.
This period of rapid economic growth and soaring prosperity in the North and the West (but not in the South) saw the U.S. become the world's dominant economic, industrial and agricultural power. The average annual income (after inflation) of nonfarm workers grew by 75% from 1865 to 1900, and then grew another 33% by 1918.
Some northern and southern states
Answer would be D)abolition
John D. Rockefeller, he created Standard oil and used a system of horizontal integration, which really hurt the consumer but it made him rich. He was basically a terrible person but a genius businessman (he would have been a trillionaire by today's standards) :)