Please answer the following question: Mahamadou Issoufou - Mahamadou Issoufou (born 1952) is a Nigerien politician who has been President of Niger since 7 April 2011. Issoufou was Prime Minister of Niger from 1993 to 1994 President of the National Assembly from 1995 to 1996 and he has been a candidate in each presidential election since 1993. He led the Nigerien Party for Democracy and Socialism (PNDS-Tarayya) a social democratic party from its foundation in 1990 until his election as President of Niger in 2011. 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