Given the question: Irvin B. Nathan - Irvin B. Nathan is the current Attorney General of the District of Columbia. He was appointed in 2011 by Mayor Vincent C. Gray. He previously served as the General Counsel of the United States House of Representatives from 2007 to 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?
The answer is:
Office Holder