System.Object
   DataDynamics.ActiveReports.Chart.Item
      DataDynamics.ActiveReports.Chart.DrawCustomizableItem
         DataDynamics.ActiveReports.Chart.MouseEnabledItem
            DataDynamics.ActiveReports.Chart.MouseEnabledComponent
               DataDynamics.ActiveReports.Chart.Annotations.Annotation
                  DataDynamics.ActiveReports.Chart.Annotations.AnnotationLine
                  DataDynamics.ActiveReports.Chart.Annotations.AnnotationTextBar
   System.Collections.CollectionBase
      DataDynamics.ActiveReports.Chart.Annotations.AnnotationsCollection

Reference

ActiveReports.Chart Assembly