What format must custom prompts be in for use during a Digital Receptionist announcement?

Custom prompts for use during a Digital Receptionist announcement must be in a specific audio format to ensure compatibility and optimal performance within the system. The correct format consists of MP3 files that are encoded in PCM (Pulse Code Modulation), at a frequency of 8 kHz, with a 16-bit depth, and in mono sound.

This particular configuration is ideal because it balances the quality of audio output with the requirements of a Digital Receptionist. The lower sampling rate and mono format keep file sizes manageable while still producing clear and comprehensible announcements. Such specifications are common in telephony applications, where clarity over telephone lines is paramount.

In contrast, the other formats and specifications mentioned do not meet the requirements for Digital Receptionist prompts. WAV files in stereo with a higher sampling rate may provide higher quality sound, but they exceed the necessary requirements, which can lead to larger file sizes and potential compatibility issues. OGG files encoded at a different frequency would not be supported, and the MP3 configurations listed in the other choices either have stereo output or incorrect sampling rates that would not be suitable for the use case.