Question: When switching from Super Wideband to Wideband in EVS (Enhanced Voice Services) codec, which scheme is employed to generate the SHB (Super High Band) signal if the conditions for TBE (Time-Bandwidth Expansion) mode are not satisfied and the core coding is not MDCT (Modified Discrete Cosine Transform)?
Option 1: AMR-WB (Adaptive Multi-Rate Wideband) Interpolation
Option 2: Multi-mode FD BWE (Frequency Domain BandWidth Extension)
Option 3: CELP (Code-Excited Linear Prediction) Extrapolation
Option 4: LPC (Linear Predictive Coding) Transformation
Explanation: According to the provided context, when switching from Super Wideband to Wideband, if the conditions for TBE mode are not met, the multi-mode FD BWE algorithm is applied to generate the SHB signal. This highlights the role of FD BWE in seamlessly adapting to bandwidth changes in Enhanced Voice Services, ensuring optimal audio quality across different network conditions.