Which of the following documents outlines the foundation of the United States government?

The Constitution serves as the foundational document of the United States government. It was adopted in 1787 and established the framework for the federal government, outlining the separation of powers among the three branches: legislative, executive, and judicial. The Constitution also defines the system of checks and balances that ensures no single branch becomes too powerful. Additionally, it includes the process for amending the document, allowing for the evolution of governance over time.

While the Declaration of Independence is a crucial historical document that announced the colonies' separation from British rule and expressed the principles of individual rights and liberties, it does not establish the framework for governance itself. The Bill of Rights, a set of amendments to the Constitution, protects certain individual liberties but is not the structural foundation of government. The Articles of Confederation served as the first constitution for the newly independent states but ultimately proved ineffective in governing, leading to the adoption of the current Constitution. Thus, the Constitution is rightly identified as the document that outlines the foundation of the United States government.