Which department coordinates and supervises all agencies and functions of the federal government concerned with national security and the armed forces?

• A. Department of Defense
• B. Health and Human Services
• C. National Institutes of Health
• D. Indian Health Service

Answer: (A)

The key idea here is which federal department oversees national security and the armed forces. The Department of Defense is the entity responsible for coordinating and supervising all agencies and functions related to national security and the military. It oversees the military services—the Army, Navy, Air Force, Marines, and Space Force—and coordinates defense policy, resources, and operations across the government as needed to protect the nation. The other options focus on health services and medical research and do not govern national security or military operations, so they don’t fit this role.