Question: Brian Olsen was the last WEC Champion before it was purchased by which sports promotion company?

Context paragraphs:
Railways Sports Promotion Board: Railways Sports Promotion Board (RSPB, originally called "Railways Sports Control Board") is a sports board run by the Indian Railways.  It promotes 29 sporting disciplines and owns the Karnail Singh Stadium in New Delhi.

Song Xiaobo: Song Xiaobo (; born September 8, 1958 in Beijing), is a basketball player and basketball coach from Beijing, China.  She is perhaps the most celebrated woman basketball player of the 1970s era in China; as a player she had outstanding all around ball skills, a very high level of athleticism, and a clear, bright, driving work ethic.  Song was outstanding at every position from guard to center and she enjoys acclaim as "China's greatest female basketball player of all time".  She is currently the CEO of a sports promotion company in Beijing.

2016 FIA World Endurance Championship: The 2016 FIA World Endurance Championship season was the fifth edition of the FIA World Endurance Championship auto racing series co-organised by the Fédération Internationale de l'Automobile (FIA) and the Automobile Club de l'Ouest (ACO).  The series was open to Le Mans Prototypes and grand tourer-style racing cars meeting four ACO categories.  The season began at the Silverstone Circuit in April and ended at the Bahrain International Circuit in November, and included the 84th running of the 24 Hours of Le Mans. This season is also the last WEC season for Audi Sport Team Joest as they decided not to race in the 2017 FIA World Endurance Championship Season.

Paulo Filho: Paulo Fernando de Souza Leite Filho, better known as simply Paulo Filho (] ; born May 24, 1978), is a Brazilian mixed martial artist currently competing in the Middleweight division.  Filho was the last WEC Middleweight Champion, and has also competed in PRIDE, DREAM, Pancrase, DEEP, Impact FC, and the World Series of Fighting.

Iron Mike Productions: Iron Mike Productions (formerly Acquinity Sports) was a boxing promotion company, based in Deerfield Beach, Florida, United States.  Acquinity Sports was founded in 2012 by Garry Jonas, CEO of Acquinity Interactive.  Jonas partnered with former heavyweight champion Mike Tyson in 2013, and changed the name of the company to Iron Mike Productions.  They represent a diverse roster of boxers., including two-time Iraq War Veteran and undefeated Sammy Vazquez, Jr., Ukrainian amateur world champion, Ivgen Khytrov, super bantamweight champion JC Payano, and top U.S. amateur prospect, Erickson Lubin.

International Sports Promotion Society: International Sports Promotion Society (国際スポーツ振興協会 , "Kokusai Spōtsu Shinkō Kyoukai" ) (ISPS, also known as ISPS Handa) is a Japanese non-profit organization known for sponsorship of the PGA Seniors Championship and LPGA Women's Australian Open tournaments and promotion of dedicated to promoting the involvement of the visually disabled in golfing.  ISPS Handa supports blind golf worldwide.  ISPS Handa is a member of the Tokyo Sports Association, a public interest incorporated foundation.  The founder Haruhisa Handa is known for promoting Blind Golf and introducing blind golf to Japan.  ISPS is committed to promote disabled golf to be adopted as an official event of the Paralympics.

Smash (professional wrestling): Smash was a Japanese puroresu and combat sports promotion, founded in December 2009 following the folding of Hustle.  In the fall of 2009 Hustle ran into financial problems that led to several show cancellations.  After a planned restructuring and restarting of the promotion failed, a number of officials and wrestlers decided to start a new project.  Smash held its first show on March 26, 2010.

Zuffa: Zuffa, LLC ( ) is an American sports promotion company specializing in mixed martial arts.  It was founded in January 2001 in Las Vegas, Nevada, by Station Casinos executives Frank Fertitta III and Lorenzo Fertitta to be the parent entity of the Ultimate Fighting Championship (UFC) after they purchased it from the Semaphore Entertainment Group.  The word "Zuffa" is an Italian word (] ), meaning "fight".  On July 11, 2016, Zuffa announced that it would be purchased by WME-IMG for the price of $4 billion.

Brian Olsen: Brian Olsen (born 1975) is an American former mixed martial artist who fought mainly in World Extreme Cagefighting.  He was the last WEC Heavyweight Champion before it was abolished when Zuffa purchased the organization.

WEC 20: WEC 20: Cinco de Mayhem was a mixed martial arts event held by World Extreme Cagefighting that took place on May 5, 2006 at Tachi Palace Hotel & Casino in Lemoore, California.  "WEC 20"'s main event was a heavyweight bout between Brian Olsen and Mike Kyle.

Supporting paragraphs: Brian Olsen Zuffa
Answer: Zuffa, LLC