The best answer is A. Keynesian economics refers to the practice of pumping money into a country's economy. In Keynesian economics that money is usually acquired from taxpayers, loans, bonds, and additional currency printing. The theory is that spending money on things like infrastructure projects (building roads, power plants, dams, etc.) creates jobs, which helps get money circulating in the economy again, which eventually pulls a country out of economic stagnation.
The second bank and tariffs help meet economic challenges because it gave the country a more stable national currency. This was because of mass marketing.
