Please answer the following question: Information:  - The Rugby Football Union (RFU) is the governing body for rugby union in England. It was founded in 1871, and was the sport's international governing body prior to the formation of what is now known as World Rugby (WR) in 1886. It promotes and runs the sport, organises international matches for the England national team, and educates and trains players and officials.  - Rugby league football, usually called rugby league, is a full contact sport played by two teams of thirteen players on a rectangular field. One of the two codes of rugby football, it originated in England in 1895 as a split from the Rugby Football Union over the issue of payments to players. Its rules gradually changed with the aim of producing a faster, more entertaining game for spectators.  - England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west. The Irish Sea lies northwest of England and the Celtic Sea lies to the southwest. England is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain (which lies in the North Atlantic) in its centre and south; and includes over 100 smaller islands such as the Isles of Scilly, and the Isle of Wight.  - Contact sports are sports that emphasize or require physical contact between players. Some sports, such as mixed martial arts, are scored on impacting an opponent, while others, including rugby football, require tackling of players. These sports are often known as full-contact, as the sport cannot be undertaken without contact. Other sports have contact, but such events are illegal under the rules of the game or are accidental and do not form part of the sport.  - Nathan Hines ( born 29 November 1976 ) is an Australian - born former Scottish international rugby player . He is also a former rugby league player , Hines played for North Sydney Bears XIII in Australia .  - Rugby is a type of football developed at Rugby School in Rugby, Warwickshire, one of many versions of football played at English public schools in the 19th century. The two main types of rugby are rugby league and rugby union. Although rugby league initially used rugby union rules, they are now wholly separate sports.    Given the information above, choose from the list below the object entity that exhibits the relation 'sport' with the subject 'nathan hines'.  Choices: - martial arts  - mixed martial arts  - rugby  - rugby league  - rugby union  - united kingdom
A:
rugby union