Question: What man, widely considered to be the greatest sprinter of all time, participated in the 2012 Summer Olympics?

full_context: Document 1: Shawn Crawford: Shawn Crawford (born January 14, 1978) is a retired American sprint athlete. He competed in the 100 meters and 200 meters events. He won gold at the 2004 Summer Olympics and silver at the 2008 Summer Olympics in the 200 meters. He originally finished 4th in the race but after the 2nd and 3rd-place winners were disqualified, he moved up to a silver. On April 18, 2013, Crawford was suspended for two years for missing out-of-competition drug tests. His coach, Bob Kersee claimed that Crawford retired after the 2012 United States Olympic Trials and USA Track & Field said he filed retirement papers in 2013.
Document 2: Colin Jackson: Colin Ray Jackson, CBE (born 18 February 1967) is a Welsh former sprint and hurdling athlete who specialised in the 110 metres hurdles. During a career in which he represented Great Britain and Wales, he won an Olympic silver medal, became world champion twice, World indoor champion once, went undefeated at the European Championships for 12 years and was a two-time Commonwealth champion. His world record of 12.91 seconds for the 110m hurdles stood for over a decade and he remains the 60 metres hurdles world record holder.
Document 3: Dina Asher-Smith: Dina Asher-Smith (born 4 December 1995) is a British sprinter who holds the British records for both the 100 metres and 200 metres. In the 4 x 100 metres relay, she won bronze medals at the 2016 Olympic Games and the 2013 World Championships. She is also the 2016 European Champion at 200 metres, the 2014 World Junior Champion at 100 metres, and the 2013 European Junior Champion at 200 metres.
Document 4: Florence Griffith Joyner: Florence Delorez Griffith Joyner (December 21, 1959 – September 21, 1998), also known as Flo-Jo, was an American track and field athlete. She is considered the fastest woman of all time based on the fact that the world records she set in 1988 for both the 100 m and 200 m still stand. During the late 1980s she became a popular figure in international track and field because of her record-setting performances and flashy personal style.
Document 5: Great Britain at the 2012 Summer Paralympics: Great Britain competed at the 2012 Summer Paralympics in London, United Kingdom, from 29 August to 9 September 2012 as the host nation. A total of 288 athletes were selected to compete along with 13 other team members such as sighted guides. The country finished third in the medals table, behind China and Russia, winning 120 medals in total; 34 gold, 43 silver and 43 bronze. Multiple medallists included cyclist Sarah Storey and wheelchair athlete David Weir, who won four gold medals each, and swimmer Stephanie Millward who won a total of five medals. Storey also became the British athlete with the most overall medals, 22, and equal-most gold medals, 11, in Paralympic Games history. To commemorate the achievements of each gold medallist Royal Mail painted a post box gold, usually in the athlete's home town.
Document 6: Great Britain at the 2012 Summer Olympics: Great Britain, represented by the British Olympic Association (BOA), competed at the 2012 Summer Olympics in London, United Kingdom, from 27 July to 12 August 2012 as the host nation. British athletes have competed at every Summer Olympic Games in the modern era, alongside Australia, France and Greece, though Great Britain is the only one to have won at least one gold medal at all of them. London is the only city to host the Summer Olympics on three different occasions, having previously done so in 1908 and 1948. Soon, it will be joined by Paris in 2024 and Los Angeles in 2028 in hosting the Olympic Games for a third time. Team GB, organised by BOA, sent a total of 541 athletes, 279 men and 262 women, to the Games, and won automatic qualification places in all 26 sports.
Document 7: Trinidad and Tobago at the 2012 Summer Olympics: Trinidad and Tobago competed at the 2012 Summer Olympics in London, United Kingdom from 27 July to 12 August 2012. This was Trinidad and Tobago's most successful Summer Olympics. It was the nation's largest ever delegation sent to the Olympics, with a total of 30 athletes, 21 men and 9 women, in 6 sports. Trinidad and Tobago's participation in these games marked its sixteenth Olympic appearance as an independent nation, although it had previously competed in four other games (including the 1948 debut in the same host city London) as a British colony, and as part of the West Indies Federation. The nation was awarded four Olympic medals based on the efforts by the athletes who competed in the track and field. Javelin thrower Keshorn Walcott became the first Trinidadian athlete to win an Olympic gold medal since the 1976 Summer Olympics in Montreal, where Hasely Crawford won for the sprint event. Marc Burns, a four-time Olympic athlete and a relay sprinter who led his team by winning the silver medal in Beijing, was the nation's flag bearer at the opening ceremony.
Document 8: 2012 Summer Olympics: The 2012 Summer Olympics, formally the Games of the XXX Olympiad and commonly known as London 2012, was a major international multi-sport event celebrated in the tradition of the Olympic Games, as governed by the International Olympic Committee (IOC). It took place in London and to a lesser extent across the United Kingdom from 25 July to 12 August 2012. The first event, the group stage in women's football began on 25 July at the Millennium Stadium in Cardiff, followed by the opening ceremonies on 27 July. 10,768 athletes from 204 National Olympic Committees (NOCs) participated.
Document 9: Maurice Greene (athlete): Maurice Greene (born July 23, 1974) is an American former track and field sprinter who specialized in the 100 meters and 200 meters. He is a former 100 m world record holder with a time of 9.79 seconds. During the height of his career (1997–2004) he won four Olympic medals and was a five-time World Champion. This included three golds at the 1999 World Championships, a feat which had previously only been done by Carl Lewis and Michael Johnson and has since been equaled by three others.
Document 10: Elaine Thompson: Elaine Thompson (born 28 June 1992) is a Jamaican track and field sprinter. She rose to prominence as part of the gold medal-winning team in the 4x100 metres relay at the 2015 World Championships, where she also won a silver medal in the 200 metres. At the 2016 Olympic Games in Rio de Janeiro, Thompson completed a rare sprint double when she won gold in the 100m (with a time of 10.71 s) and the 200m (21.78 s), becoming the first female sprinter to do so since Florence Griffith Joyner at the Seoul Olympics in 1988. Thompson currently ranks as the fifth-fastest woman ever in the 200 metres event and tied fourth-fastest in the 100 metres.
Document 11: Somalia at the 2012 Summer Olympics: Somalia participated at the 2012 Summer Olympics in London, United Kingdom, which took place from 27 July to 12 August 2012. The country's participation in London marked its ninth appearance in the Summer Olympics since its debut at the 1972 Summer Olympics. The delegation included one short-distance sprinter and one long-distance runner: Mohamed Hassan Mohamed and Zamzam Mohamed Farah. Both qualified for the games through wildcard places from the International Association of Athletics Federations. Farah was selected as the flag bearer for both the opening and closing ceremonies. Mohamed and Farah failed to advance beyond the heat stage of their respective events.
Document 12: Jamaica at the 2012 Summer Olympics: Jamaica competed at the 2012 Summer Olympics in London, from 27 July to 12 August 2012. This was Jamaica's most successful performance in the Summer Olympics; it was approximately the same size from the previous games with a delegation of 50 athletes (25 men and 25 women), and its athletes broke the nation's record for the number of medals (all awarded in the track and field), won in a single games. Jamaica's participation in London marked its sixteenth appearance as an independent nation, although it had previously competed in four other games (including the 1948 debut in the same host city London) as a British colony, and as part of the West Indies Federation. Usain Bolt became the nation's greatest highlight of these games, having won three of Jamaica's four gold medals at London, and breaking an Olympic and world record in two of the three events in which he participated. Because of his repeated successes for the most medals and records, Bolt became Jamaica's first male flag bearer at the opening ceremony since 1984.
Document 13: Usain Bolt: Usain St Leo Bolt ( ; born 21 August 1986) is a retired Jamaican sprinter. He is the first person to hold both the 100 metres and 200 metres world records since fully automatic time became mandatory. He also holds the world record as a part of the 4 × 100 metres relay. He is the reigning Olympic champion in these three events. Because of his dominance and achievements in sprint competition, he is widely considered to be the greatest sprinter of all time.
Document 14: Tim Montgomery: Timothy "Tim" Montgomery (born January 28, 1975) is an American former track and field sprinter who specialized in the 100-meter dash. In 2005, he was stripped of his records—including a now void men's 100 m world record of 9.78 seconds set in 2002—after being found guilty of using performance-enhancing drugs as a central figure in the BALCO scandal. Since retiring from athletics, he has been tried and convicted for his part in a New York-based check fraud scheme and for dealing heroin in the Hampton Roads area of Virginia.
Document 15: Great Britain at the 1964 Summer Olympics: The United Kingdom competed as Great Britain at the 1964 Summer Olympics in Tokyo, Japan. 204 competitors, 160 men and 44 women, took part in 124 events in 17 sports. British athletes have competed and won at least one gold medal in every Summer Olympic Games. Future Liberal Democrat leader Menzies Campbell represented Britain at the 200m.
ground_truth: Usain Bolt