A selected "[Serf]" belongs to a "[King]" which cannot be added to an Option--it was not added to the Option Set.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.4.0.0 (26.4.0.0)
Syntax
C#
public static FailureDefinitionId KingNeverInOptionWarn { get; }