Virgil von Graben -  Virgil von Graben (15th century — 1507) was an Austrian noble and knight who was stadtholder of Lienz and East Tyrol and Regent (captain) and stadtholder of Görz. He also ruled four Burggrafschaften (a sort of Viscountships) in the County of Tyrol the Duchy of Carinthia and in the Archbishopric of Salzburg. Virgil von Graben was a powerful advisor to count Leonhard of Gorizia and emperor Maximilian I. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Office Holder