Given the question: 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. David Alderdice - David King Alderdice is a former Lord Mayor of Belfast and a senior member of the Alliance Party of Northern Ireland. He was elected to North Down Borough Council representing Holywood on 5 May 2005 and retired in July 2010.A dermatologist by profession he is married with three children. He is the brother of former party Leader John Alderdice the immediate past President of Liberal International.He has also run unsuccessfully for the United Kingdom House of Commons on three occasions.
The answer is:
Office Holder