Which agency is primarily responsible for the security of NCIC data?

The FBI is the agency primarily responsible for the security of NCIC data because it manages and operates the National Crime Information Center. The FBI ensures that the information stored in the NCIC database is secure, protects against unauthorized access, and maintains the integrity of the data. This responsibility includes overseeing the technological infrastructure, implementing security protocols, and providing training to authorized personnel who access NCIC data.

While other agencies, such as the Department of Homeland Security and the Department of Justice, may have involvement in broader law enforcement and national security initiatives, the FBI has the specific mandate to oversee and protect the NCIC database, making it the correct answer to this question.