Answer the following question: Information:  - Freestyle BMX is bicycle motocross stunt riding on BMX bikes. It is an extreme sport descended from BMX racing that consists of five disciplines: street, park, vert, trails, and flatland.  - A multi-sport event is an organized sports event, often held over multiple days, featuring competition in many different sports between organized teams of athletes from (mostly) nation states. The first major, modern, multi-sport event of international significance is the modern Olympic Games.  - Jamie Alan Staff MBE ( born 30 April 1973 ) is an English racing cyclist and coach , formerly on BMX and later on the track . A World and Olympic champion , he has also won numerous other medals at World Championships , World Cups and at the Commonwealth Games .  - Cycle sport is competitive physical activity using bicycles. There are several categories of bicycle racing including road bicycle racing, time trialling, cyclo-cross, mountain bike racing, track cycling, BMX, and cycle speedway. Non-racing cycling sports include artistic cycling, cycle polo, freestyle BMX and mountain bike trials. The Union Cycliste Internationale (UCI) is the world governing body for cycling and international competitive cycling events. The International Human Powered Vehicle Association is the governing body for human-powered vehicles that imposes far fewer restrictions on their design than does the UCI. The UltraMarathon Cycling Association is the governing body for many ultra-distance cycling races.  - The Commonwealth Games (known as the British Empire Games from 19301950, the British Empire and Commonwealth Games from 19541966, and British Commonwealth Games from 19701974) is an international, multi-sport event involving athletes from the Commonwealth of Nations. The event was first held in 1930, and, with the exception of 1942 and 1946, which were cancelled due to World War II, has taken place every four years since then.  - BMX racing is a type of off-road bicycle racing. The format of BMX was derived from motocross racing. BMX bicycle races are sprint races on purpose-built off-road single-lap race tracks. The track usually consists of a starting gate for up to eight racers, a groomed, serpentine, dirt race course made of various jumps and rollers and a finish line. The course is usually flat, about wide and has large banked corners that help the riders maintain speed.  The sport of BMX racing is facilitated by a number of regional and international sanctioning bodies. They provide rules for sanctioning the conduct of the flying, specify age group and skill-level classifications among the racers, and maintain some kind of points-accumulation system over the racing season. The sport is very family oriented and largely participant-driven, with riders ranging in age from 2 to 70, and over. Professional ranks exist for both men and women, where the age ranges from 18 to 40 years old.  - A BMX bike is an off-road sport bicycle used for racing and stunt riding. BMX means bicycle motocross.  - The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom and its predecessor states. It originated with the overseas possessions and trading posts established by England between the late 16th and early 18th centuries. At its height, it was the largest empire in history and, for over a century, was the foremost global power. By 1913, the British Empire held sway over 412 million people, % of the world population at the time, and by 1920, it covered , % of the Earth's total land area. As a result, its political, legal, linguistic and cultural legacy is widespread. At the peak of its power, the phrase "the empire on which the sun never sets" was often used to describe the British Empire, because its expanse around the globe meant that the sun was always shining on at least one of its territories.  - Motocross is a form of off-road motorcycle racing held on enclosed off-road circuits. The sport evolved from motorcycle trials competitions held in the United Kingdom.  - BMX, an abbreviation for bicycle motocross, is a cycle sport performed on BMX bikes, either in competitive BMX racing or freestyle BMX, or else in general on- or off-road recreation. BMX began when young cyclists appropriated motocross tracks for fun, racing and stunts, eventually evolving specialized BMX bikes and competitions.    What object entity has the relation of 'sport' with the subject 'jamie staff'?   Choices: - bicycle motocross  - cycle sport  - motocross  - road bicycle racing  - sport  - sprint  - ultramarathon  - united kingdom
Answer:
bicycle motocross