Right-clicking on a region, mesh assembly, 3D primitive, or 2D primitive in the tree view displays a shortcut menu containing various options depending on what is selected. For details about the generic shortcut menu commands, see Outline Tree View Shortcut Menu Commands. Details about the mesh-related shortcut menu items are provided in:
Note: If Highlighting 
is selected (from the viewer toolbar), mesh entities
will be highlighted in the viewer when you select them in the tree
view.