Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Elmer Ernest Roper -  Elmer Ernest Roper (June 4 1893 – November 12 1994) was a politician in Alberta Canada. He served as leader of the Alberta Co-operative Commonwealth Federation the mayor of Edmonton and a member of the Legislative Assembly of Alberta. He was also a candidate for the Canadian House of Commons.
A:
Office Holder