Q:Sancaktar Hayrettin Mosque (Turkish: Sancaktar Hayrettin Camii; also Sancaktar Hayrettin Mescidi where Mescit is the Turkish word for a small mosque or Sancaktar Mescidi) is part of a former Eastern Orthodox monastery converted into a mosque by the Ottomans. It is generally believed that the small building belonged to the Byzantine Monastery of Gastria (Greek: Mone ton Gastrion meaning Monastery of the Vases). Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Building