What is the national bibliography of the United States called?

The national bibliography of the United States is referred to as the National Union Catalog. This catalog serves as a comprehensive listing of the names and titles of books for which libraries across the United States hold records. It aggregates bibliographic information from countless libraries and institutions, thereby providing a centralized resource that helps researchers and librarians identify the availability of books and other media within the U.S.

The National Union Catalog is particularly important for various purposes such as resource sharing, cataloging, and preserving cultural heritage, as it reflects the collective holdings of libraries. The other choices, while they may sound plausible, do not represent a recognized national bibliography, illustrating the unique role the National Union Catalog plays in the context of U.S. bibliographic data.