Dept. that oversees the F.D.A.

HHS

This cabinet-level agency focuses on health and human services nationwide.

The clue refers to the U.S. government department responsible for the Food and Drug Administration (F.D.A.). That department is Health and Human Services, commonly abbreviated as HHS. It’s a straightforward abbreviation clue where "Dept." signals you’re looking for a short form of the agency’s name.