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. Conquistador Cielo -  Conquistador Cielo (March 20 1979–December 17 2002) was an American Thoroughbred racehorse. He is best known for his performances as a three-year-old in 1982 when he won the Belmont Stakes and was voted United States Horse of the Year.
The answer is:
Animal