Why did qin shihuangdi force all nobles to live at the capital?

The correct answer is:

Qin Shihuangdi forced all the nobles to live at the capital so he could have a close eye on them. "He knew it would reduce rebellion and infighting"

Explanation:

Confucius was a Chinese maestro and scholar of the early 6th century. He was growing in following when Qin Shihuangdi was in control. Qin's authority was questioned because of Confucius' instructions and he apprehended that the nobles would overthrow him if they were too persuaded that what Confucius showed them was the right path. So he ordered all the nobles to live in the capital so he could keep a close eye them and not let them plan or radical fronting him. 

the second significant cause of the great migration was the desire of black southerners to escape segregation, known euphemistically as jim crow. rural african american southerners believed that segregation - and racism and prejudice against blacks - was significantly less intense in the north.

basic principles: federalism, separation of powers, checks and balances, judicial review, representative democracy, limited government, rule of law, individual rights and responsibilities, consent of the governed, majority rule, popular sovereignty, equal protection.