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. Bill Aldag - William 'Bill' Aldag (born 30 November 1905 date of death unknown) was an Australian rules footballer who played for Footscray and Collingwood in the Victorian Football League (VFL).Aldag had his first league season in 1928 with Footscray. In 1930 he joined Collingwood and was a half forward flanker in their 1930 premiership team.
The answer is:
Athlete