Final answer:
The Founders chose a republican form of government because it aligned with the Revolution's principles, prevented power corruption, and represented the will of the American people, ensuring a system protecting natural rights and dividing power across branches.
Step-by-step explanation:
The Founders chose a republican form of government because they believed it best suited the American people's character and the principles of the Revolution. They felt it necessary to prevent corruption by power through a separation of powers, avoiding the pitfalls of monarchy, oligarchy, and mobocracy. In Federalist #39, Madison described a republican government that derives its power from the people, administered by elected officials with limited tenures who are not from a privileged class. They also required states to uphold this representative form of government as per Article IV, Section 4 of the Constitution. Americans at that time, influenced strongly by Enlightenment thinkers such as John Locke and Baron Montesquieu, sought a government that protected natural rights and shared power across multiple branches to prevent the concentration of power in any single institution.