The introduction of the us constitution is called the
bill of rights.
articles
amendments.
preamble.

The introduction of the United States Constitution is the Preamble.

Preamble

Explanation:

The Preamble of the U.S. Constitution is a brief introduction of the Constitution that sets its fundamental purposes and guiding principles, in which are included the principles of democracy, popular sovereignty, justice, domestic tranquility, liberty, and America's general welfare. It states the following:

We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defense, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.

the answer to your question is,

d. when a child was born.

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