Which agency is primarily responsible for overseeing the compliance of NCIC data usage?

The Federal Bureau of Investigation (FBI) is primarily responsible for overseeing the compliance of NCIC data usage. The NCIC operates under the management of the FBI, which ensures that the data is used in accordance with national standards and regulations. The FBI's role encompasses maintaining the integrity and security of the system while also providing guidance and oversight to the various agencies that access and utilize NCIC data for law enforcement purposes.

Other agencies mentioned in the choices, while involved in law enforcement and data protection, do not have the specific mandate to oversee the NCIC. The Department of Homeland Security focuses more on national security and immigration issues, the U.S. Department of Justice deals with federal legal matters but does not directly manage the NCIC, and the Federal Trade Commission is primarily concerned with consumer protection and antitrust laws. Therefore, the FBI stands out as the key agency tasked with ensuring compliance and proper usage of the NCIC data.