Information: - Gisela Dulko (born 30 January 1985, in Tigre) is a retired professional tennis player from Argentina. Although she enjoyed modest success in singles, reaching world no. 26 and winning four WTA Tour titles, her speciality was doubles, where she achieved a world no. 1 ranking. Partnering with Flavia Pennetta, Dulko won the 2010 WTA Tour Championships and the 2011 Australian Open in doubles. Dulko also reached the mixed doubles final at the 2011 US Open, with Edward Schwank. She is remembered for her ability to upset the big names on the tour, such as Maria Sharapova in the second round of Wimbledon in 2009; and Samantha Stosur in the third round of Roland Garros in 2011. She also beat Martina Navratilova in the second round of Wimbledon in 2004 in Navratilova's final Grand Slam singles match. - Eduardo Jonatan Schwank ( born 23 April 1986 ) is a retired professional tennis player from Argentina . In 2011 , he reached the finals of the French Open in men 's doubles partnering Juan Sebastian Cabal and of the US Open in mixed doubles partnering Gisela Dulko . He was coached by Javier Nalbandian , the brother of David Nalbandian . Schwank 's family background is from the German - speaking part of Switzerland - Tennis is a racket sport that can be played individually against a single opponent (singles) or between two teams of two players each (doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court. The object of the game is to play the ball in such a way that the opponent is not able to play a valid return. The player who is unable to return the ball will not gain a point, while the opposite player will. - David Pablo Nalbandian (born 1 January 1982) is an Argentine retired professional tennis player and former world No. 3. He was runner-up at the 2002 Wimbledon Championships and the winner of the Tennis Masters Cup in 2005. He has also won two Masters 1000 events. Nalbandian is the only Argentine player in history who ever reached the semi-finals or better at all four Grand Slam tournaments and reached the men's singles final at Wimbledon. - Maria Yuryevna Sharapova (born April 19, 1987) is a Russian professional tennis player. A United States resident since 1994, Sharapova has competed on the WTA tour since 2001. She has been ranked world No. 1 in singles by the WTA on five separate occasions, for a total of 21 weeks. She is one of ten women, and the only Russian, to hold the career Grand Slam. She is also an Olympic medalist, having earned silver for Russia in women's singles at the 2012 Summer Olympics in London. After reading the paragraphs above, we are interested in knowing the entity with which 'eduardo schwank' exhibits the relationship of 'participant of'. Find the answer from the choices below. Choices: - 2012 summer olympics - sport
2012 summer olympics