Mediation is a voluntary, assisted negotiation process where a neutral mediator helps parties explore settlement (B). A common mediation practice is “caucusing,” where the mediator meets privately with each party separately to discuss interests, options, and settlement ranges; this is often essential to progress. Therefore, the claim that a mediator must never meet with one party in the absence of the other (C) is false. Confidentiality is a defining feature of mediation, and discussions are typically treated as “without prejudice,” meaning they generally cannot be used later in court if settlement fails (A reflects this concept, though the exact legal privilege can depend on jurisdiction and agreement terms). Attendance by party representatives (D) is generally required in practice so decisions can be made and terms can be negotiated, though the specific form (lawyer, authorized representative, insurer) depends on the dispute and mediation agreement. The key incorrect statement is C because separate meetings are a normal, accepted mediation technique.