An important scientist at the time, besides, those who were mentioned was Copernicus - A.
Spartacus was just a slave general in the Roman republic.
Rousseau was a philosopher.
Plato was a philosopher as well.
The correct answer for that reason is Copernicus, he was an astronomer and a major figure at the time.
Answer:
America was moving towards an industrialized, modern, capitalist economy:
Industrialized because industry was becoming more important than agriculture.
Modern because scientific and engineering progress were being applied to industry in order to increase production and efficiency.
Capitalist because people were producing goods for profit, not just for mere survival.
