What events led to the great wall of china being built?

Choices? im thinking spain but with no choices its a bit vague 

Well, the correct answer is to reduce federal spendingthis is because he had done a reconstruction of the system to improve it for the future of the united states, but it didn't reduce federal spending pretty much at all. the previous governments made federal spending a huge problem causing the promise to fail because it was pretty much an impossible  task.i hope this mark me as brainiest