Who is the principal staff assistant and advisor to the Secretary of Defense on all intelligence, counterintelligence (CI), security, and related intelligence matters?

• A. The USD(I) is the principal staff assistant and advisor to SecDef on all intelligence, CI and security, and other intelligence related matters
• B. The USD(I) is the principal staff assistant and advisor to SecDef on all intelligence, security, and other intelligence related matters
• C. The USD(I) is the principal staff assistant and advisor to SecDef on all intelligence, CI, and security only
• D. The USD(I) is the principal staff assistant and advisor to SecDef on all intelligence, CI and security and cyber matters

Answer: (A)

The main idea is identifying who directly advises the Secretary of Defense on all intelligence, counterintelligence, and security matters. The Under Secretary of Defense for Intelligence serves as the principal staff assistant and advisor to the Secretary of Defense for precisely that broad set of areas—intelligence, counterintelligence, security, and related intelligence matters. This role consolidates guidance and oversight across the Defense Intelligence Enterprise, ensuring policy and programs align with national security needs.

That scope matters because it includes not just pure intelligence analysis and collection, but also counterintelligence efforts and security concerns that affect personnel, information, and facilities. The other options either drop counterintelligence, or limit the scope, or add cyber in a way that isn’t part of the standard description. So the best choice accurately captures the full breadth of responsibility described.