Explanation: Phase 2 P25 radios utilize the **AMBE+2™** (Advanced Multi-Band Excitation) voice CODEC. AMBE is a proprietary voice compression algorithm developed by Digital Voice Systems, Inc. (DVSI). Its purpose is to efficiently digitize and compress analog voice signals into a digital data stream, allowing for clear and bandwidth-efficient digital communication over radio channels. While P25 Phase 1 uses IMBE (Improved Multi-Band Excitation), Phase 2 specifically employs the more advanced AMBE+2, which offers improved performance and robustness, especially when operating in the 2-slot TDMA (Time Division Multiple Access) scheme of Phase 2. The other options are incorrect: IWCE is a trade show, IMBC is not a recognized P25 CODEC, and IMMM is not related to radio CODECs.