Final answer:
The 13th, 14th, and 15th Amendments were passed to grant rights and protections to African Americans, including the abolition of slavery, granting of citizenship, and securing the right to vote for black men.
Step-by-step explanation:
The main purpose of the 13th, 14th, and 15th Amendments to the U.S. Constitution was to grant rights and protections to African Americans who had been enslaved and ensure their political equality.
The 13th Amendment abolished slavery in the United States, providing freedom for formerly enslaved individuals. The 14th Amendment granted citizenship to African Americans and ensured equal protection under the law, regardless of race or color. It also prohibited states from depriving residents of life, liberty, or property without due process of law. The 15th Amendment secured the right to vote for African American men.