Fourteenth Amendment, amendment (1868) to the Constitution of the United States that granted citizenship and equal civil and legal rights to African Americans and slaves who had been emancipated after the American Civil War, including them under the umbrella phrase “all persons born or naturalized in the United States. ...
The amendment grants citizenship to "all persons born or naturalized in the United States" which included former slaves who had just been freed after the Civil War.
The answer would be B.