Because popes and Italian nobles resented the German power over Italy.
The best answer is: Lords. Lords are noble (of high rank) and rich or else important in some way.
Peasants are the farmers, among the poorest. Merchants are the once who are engaged in trade and Artisans were skilled workers who produced specialized goods.
The correct answer is B: "The growth and development of European towns."
As a consequence of the Crusades and the initial need of shipping Christian Armies to the Middle East, long distance trade reappeared in Europe for the first time since the years of the Roman Empire. The exchange of goods between Europeans and Arabs also reintroduced the use of currency which in turn further facilitated and increased trade operations. In less than a couple of centuries, many European towns went from a subsistence economy (based on the production of the goods strictly needed in the community) to a mercantile economy in which cities produced vast amounts of wealth.
