In order to add this '[Serf]' to the Option Set, you must also add its '[King]'--if you continue it will not be added to the Option Set
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.1.0.0 (26.1.0.34)
Syntax
C#
public static FailureDefinitionId MustAddKingWarn { get; }