which element of federal government best reflects the constitutional principle of the separation of powers?

Separation of powers is a doctrine of constitutional law under which the three branches of government (executive, legislative, and judicial) are kept separate. This is also known as the system of checks and balances, because each branch is given certain powers so as to check and balance the other branches.

The main element of the aforementioned, which contributed to the understanding and the effective division of powers, is the creation of the three arms of government, based on the idea of Montesquieu: executive power (president, governors and mayors), legislative (House of the Representatives and the Senate) and judiciary (judges). This element is not only fundamental, but the essence of the division of powers, which seeks to decentralize government. So ur answer to this question The creation of three branches of government