Which of the following is NOT one of the four pillars of spectrum management?

• A. Allocation
• B. Coordination
• C. Protection
• D. Encryption

Answer: (D)

Spectrum management centers on how the radio spectrum is allocated, coordinated, and protected to prevent interference and ensure reliable service. Encryption, by contrast, is a method for securing the content of a transmission, not a mechanism for managing spectrum resources. Because the pillars address how spectrum is assigned and shared (allocation), how users coordinate to avoid conflicts (coordination), and how protections are enforced for licensed services (protection), encryption doesn’t belong to this framework. That’s why encryption is not considered one of the pillars of spectrum management.