What must be recorded on the score sheet when a Libero serves from the left side?

When recording a Libero's service from the left side, drawing a triangle around the service position is the correct action to take. This notation is specifically used to indicate that the Libero is serving from that particular area of the court. By marking this on the score sheet, it clearly communicates the specific position of the Libero during the serve, which is important for tracking substitutions and adherence to court position rules.

This method helps ensure that all participants and officials are aware of the players' positions, which is crucial for maintaining the integrity of the game and for proper officiating. The triangle serves as a visual cue that distinguishes the Libero's service position, thus preventing any confusion that could arise over player rotations and responsibilities during play.

Other options, while related to the scorekeeping process, do not specifically address the required notation for a Libero's service position in the context of this question.