I believe there are lots of reasons why the Roman Empire declined but the 3 most important ones are, Government corruption and political instability, Invasions by Barbarian tribes, and The rise of the Eastern Empire, but the one I think is the most important is the first one reason.
The correct answer is:
A) During the Crusades.
The exchange of new ideas and inventions made throughout the Crusades is considered the earliest beginning of the Renaissance.
The Crusades increased the interest in travel and discovering Europe, which may have lead to the Renaissance. Furthermore, the Crusades serviced an increment in trade and reduced the power of European Nobles, the key to bring about the Age of Exploration.
