Mary MacSwiney (pronounced 'MacSweeney'; Irish: Maire Nic Suibhne; 27 March 1872 8 March 1942) was an Irish politician and educationalist. In 1927 she became 'de facto' leader of Sinn Fein when de Valera resigned from the presidency of the party. 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?
Answer:
Office Holder