Kublai Khan made several significant contributions during his rule in China. The correct responses are:
- reorganized the government structure
- rebuilt and extended the Grand Canal
- tolerated foreign cultures and belief systems
While Kublai Khan did take measures to strengthen the Great Wall, there is not ample evidence to suggest that he specifically built the Great Wall during his reign, as its construction spanned multiple dynasties. The other responses about the Great Wall are misleading in the context of his direct contributions.