C. Separation of powers although I guess it also ties in with checks and balances and the branches of the government
Okay, so back in the days, when a debtor owed money to person, the debtor would pay back the debt by working under the person as an indentured servant. While he works under this person, he wouldn't earn any more, because he's paying off his debt. Once the debt is payed off, the guy can go back to his own life.
The Founding Fathers were influenced by Montesquieu when making the constitution. Mostly because of his idea of the separation of powers.
Answer:
Timbuktu was part of Songhai and Mali.