What is the difference between primary, secondary, and adjacent sectors in air defense operations?

What is the difference between primary, secondary, and adjacent sectors in air defense operations?

• A. Primary sector is the main responsibility, secondary supports when needed, and adjacent sectors provide coverage and deconfliction.
• B. Primary and secondary have the same duties; adjacent sectors are the primary only.
• C. Adjacent sectors have no role.
• D. Primary sector is the main responsibility, secondary supports when needed, and adjacent sectors provide coverage and deconfliction.

Answer: (D)