This box shows the objects that were selected for the export. These objects, including their content and dependent objects, will be exported. Note that objects in the ITP/MDK Repository almost always contain other objects, are associated with other objects, or use other objects. Because of this, the starting set represents the export starting points and not what is actually exported. The exported set will be much larger because the Export mechanism will export everything needed to recreate the ITP Models in the starting set.
However, in case the option "Select exported objects by label" is selected, the starting set merely acts as the set in which is sought for the revisions that are to be exported, i.e., the revisions that carry the specified label. Now these selected revisions act as the core of the export set, although that still will be extended with objects needed to get a sound collection.