The correct answer is: "Checks and balances between branches of government".
The system of 'Checks and Balances' is directly derived from the principle of the division of powers, introduced by the Enlightment phyloshopher Montesquieu. Such principle indicates how the power of a state needs to be divided in three branches: legislative, executive and judiciary. Moreover, each of the branches needs to be supervised, to make sure that it does not concentrate too much power to overrrule the others. Thefore, the most efficient manner to organize that supervision duties is designing a mechanism through which each branch monitors the other two.
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