Adding the story would have been a good idea for others to help you.
The Mongols had a benevolent attitude toward foreign religions, or at least a policy of benign neglect. Their belief in Shamanism notwithstanding, the Mongols determined early on that aggressive imposition of their native religion on their subjects would be counter-productive.
I believe it would be politics, education, and voting right
A. the amount of time they spent building the wall
I think the answer is A, when I looked at the picture and did some research, I found that the wall is 70 miles long so it's pretty obvious that they spent a lot of time making it in ancient old times.
