Which radio system uses a shared pool of channels assigned as needed to users?

• A. UHF
• B. Trunked system
• C. VHF
• D. Duplex

Answer: (B)

A system that uses a shared pool of channels assigned as needed to users is a trunked radio system. In trunking, all channels are part of one central pool, and when someone wants to communicate, the system quickly allocates an available channel from that pool and sets up the call through a control function. This dynamic assignment maximizes efficiency and capacity because channels aren’t tied to individual users or groups; they’re reused as soon as a transmission ends, allowing many users to share a finite number of channels.

Understanding the other options helps clarify why this fits trunking. The terms UHF and VHF refer to frequency bands, not how channels are managed; they can be used in either conventional or trunked systems but don’t describe the shared-pool concept by themselves. Duplex describes a method of two-way communication using paired frequencies (uplink and downlink) and isn’t about how channels are allocated or shared among users.