"c) rise in the demand for consumer goods" is the best option in terms of what affected the American economy immediately after world war 1, since this was a time of great prosperity.
One can be gunpowder that was borrowed from China, which includes things like fireworks. Another can be numbers that were borrowed from Arabic and Hindu cultures, the basic system of 0-9. There were many more but these are quite common and have been around for a long time.
B is the correct answer the Indian Ocean trade
The fertility and the environment in the Andes make it more suitable for beans, tubers, and grains. Crops grown in the Pampas include a much wider variety.