Final answer:
The Crusades provided new economic opportunities for the lower and middle classes through trade in Europe.
Step-by-step explanation:
The Crusades had a significant impact on the class system in Europe. One of the main effects was that the lower and middle classes found new opportunities for wealth and social mobility through trade. As trade grew, people of all classes had the chance to increase their income and improve their social status.
However, it is important to note that the Crusades did not lead to complete equality or a decrease in the wealthy and merchant classes. Instead, it created opportunities for upward mobility for some individuals, but did not significantly change the overall class structure.
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