The origin of the concept of separation of powers is most associated withGroup of answer choicesde Tocqueville.Montesquieu.Locke.none of the above.Machiavelli.

The concept of separation of powers is most popularly associated with Montesquieu. In his work "The Spirit of the Laws," published in 1748, Montesquieu articulated the idea that the political authority of a state should be divided into different branches to prevent any one group from gaining too much power. This theory emphasized the importance of checks and balances among the legislative, executive, and judicial branches, which has profoundly influenced many modern democratic systems.

In contrast, while figures like Locke and Machiavelli contributed to political philosophy, their work does not center specifically on the separation of powers as a structured concept. Thus, the correct answer would be:

Montesquieu.