A. introduces the main ideas of the constitution.
The Preamble of the U.S. Constitution serves as an introductory statement that outlines the purpose and goals of the Constitution. It does not provide a detailed explanation of how the government will work, nor does it list the ways the Constitution has been changed. Instead, it presents a broad overview of the principles that underlie the Constitution, such as establishing justice, ensuring domestic tranquility, providing for the common defense, promoting the general welfare, and securing the blessings of liberty to ourselves and our posterity. While the Preamble does not specifically describe the three branches of government, it does suggest the importance of establishing a system of government that is designed to promote the common good and protect the rights of the people.