What is the opening sentence of the U.S. Constitution called?

The opening sentence of the U.S. Constitution is called the Preamble. It serves as an introduction to the Constitution and outlines the fundamental purposes and guiding principles of the document. The Preamble famously begins with the phrase "We the People," indicating that the authority of the government is derived from the people. It sets the tone for the rest of the Constitution by expressing the goals of establishing justice, promoting the general welfare, and securing the blessings of liberty for both current and future generations.

Other options do not describe the opening of the Constitution. The Bill of Rights refers to the first ten amendments that list specific rights and protections for individuals. The Declaration commonly refers to the Declaration of Independence, which is a separate historical document that proclaimed the colonies' separation from British rule. The Articles typically mention the Articles of Confederation, the first governing document of the United States, which preceded the Constitution. Each of these terms represents different aspects or documents in American history, but none refers to the opening sentence of the Constitution.