Which document contains the Elastic Clause?

The Elastic Clause, also known as the Necessary and Proper Clause, is found in the U.S. Constitution, specifically in Article I, Section 8. This clause grants Congress the power to pass all laws deemed necessary and proper for carrying out its enumerated powers. The flexibility of this clause allows the federal government to adapt and enact legislation that responds to changing circumstances and needs beyond those explicitly outlined in the Constitution.

Since the Elastic Clause enables Congress to effectively implement its responsibilities, it has played a significant role in expanding the powers of the federal government over time. The other documents listed do not contain this clause; for instance, the Declaration of Independence primarily establishes the principles of individual rights and government legitimacy, the Bill of Rights enumerates individual liberties and protections against government overreach, and the Articles of Confederation laid out a framework for a weaker central government without such expansive powers. Therefore, the U.S. Constitution is the correct answer, as it is the foundational document that establishes the structure and powers of the government.