Along with the diminishing supply of metals used for currency, Chines scholars developed the new economic idea that held paper money as a means of payment and exchange, not as a value in itself. The issuing of paper currency in Song China was as much of a process as the invention of paper currency itself.
Answer:
A: They were independent of one another.
Explanation:
Contrary to popular belief, the Maya were not a single people, but several peoples (ethnicities) who had the same linguistic and cultural origin, and inhabited Mesoamerica.
D. Western European crusaders conquered the Muslim empires and enslaved most of the people.
The answer is A) concentrated within a small upper class
