Which channels should never be combined in a four-channel recording system?

In a four-channel recording system, maintaining clear audio separation of different speakers is essential for accurate transcription and clarity in legal proceedings. The choice that delivers the best practice involves keeping all critical voices distinct and identifiable.

When combining the presiding official, the witness, and both counsel tables into one channel, you run the risk of losing clarity in the recording. This is crucial because the presiding official's instructions, the witness's testimony, and the attorneys' arguments hold distinct significance in court. If all these voices are recorded on a single channel, it can become confusing to distinguish who is speaking at any given moment, which can lead to misunderstandings during transcription and review.

Conversely, the other choices either involve fewer parties or maintain a clearer distinction between different roles in the courtroom. For example, combining the presiding official with just one witness or one counsel table means fewer voices are at stake, typically allowing for better clarity. Hence, option C is the most problematic in terms of audio clarity and legal integrity in recordings, making it the correct answer.