Question: What US state is the KeyArena located in where the Ultimate Fighting Championship holds events?

Context paragraphs:
Michael Johnson (fighter): Michael Julian Johnson (born June 4, 1986) is an American mixed martial artist who competes in the lightweight division of the Ultimate Fighting Championship.  A professional MMA competitor since 2008, Johnson mostly competed in his regional circuit, before signing onto the Ultimate Fighting Championship to appear on "".  As of July 2017, he is #9 in the official UFC lightweight rankings.

Harold Howard: Harold Clarence Howard (born 1958) is a retired Canadian martial artist who earned a blackbelt in jujutsu under Steve Reynolds and in Gōjū-ryū karate under Yogi Israel and was the first World Sport Jujutsu Heavyweight Champion in 1984.  Howard is more widely known for competing in the Ultimate Fighting Championship where he made it to the final of the Ultimate Fighting Championship's third tournament.  Howard is also well known for once executing a scissor-flip kick during his battle with Steve Jennum in the UFC 3 finals.

UFC 2: The Ultimate Fighting Championship Part II (later renamed UFC 2: No Way Out) was a mixed martial arts (MMA) event held by the Ultimate Fighting Championship (UFC) on March 11, 1994, at Mammoth Gardens in Denver, Colorado.  The event was seen live on pay-per-view in the United States, and was later released on home video.

Devin Clark (fighter): Devin "Brown Bear" Clark (born April 2, 1990) is an American mixed martial artist.  He was signed by Ultimate Fighting Championship (UFC) after Dana White scouted him on the "Dana White: Looking for a Fight - Season 1 Episode 6" UFC web series.  He is currently competing in the light heavyweight division with Ultimate Fighting Championship.

Ultimate Fighting Championship (video game): Ultimate Fighting Championship is the first video game based on the Ultimate Fighting Championship mixed martial arts tournament.  It was first developed by Anchor Inc. for the Sega Dreamcast on August 29, 2000, then by Opus for the Sony PlayStation on November 13 the same year, and finally by Fluid Studios for the Game Boy Color on November 27 the same year.  All three versions were published by Crave Entertainment.

UFC 3: The Ultimate Fighting Championship III (later renamed UFC 3: The American Dream) was a mixed martial arts (MMA) event held by the Ultimate Fighting Championship (UFC) on September 9, 1994, at Grady Cole Center in Charlotte, North Carolina.  The event was seen live on pay-per-view in the United States, and was later released on home video.

UFC Fight Night: Nogueira vs. Davis: UFC Fight Night: Nogueira vs. Davis (also known as UFC Fight Night 24) was a mixed martial arts event held by the Ultimate Fighting Championship on March 26, 2011 at the KeyArena in Seattle, Washington.

Antônio Rodrigo Nogueira: Antônio Rodrigo Nogueira (] , born June 2, 1976), better known as Minotauro, is a semi-retired Brazilian mixed martial artist known for his technical mastery of Brazilian jiu-jitsu.  He won most of his fights via submissions.  He competed in the heavyweight division of the Ultimate Fighting Championship (UFC), where he is a former Interim UFC Heavyweight Champion.  He is the twin brother of UFC fighter Antônio Rogério Nogueira.  Nogueria rose to prominence in the Japanese promotion Pride Fighting Championships, where he was the first Pride Heavyweight Champion from November 2001 to March 2003, as well as a 2004 PRIDE FC Heavyweight Grand Prix Finalist.  He is one of only three men to have held championship titles in both Pride Fighting Championships and the Ultimate Fighting Championship (the others being Mauricio Rua and Mark Coleman).

KeyArena: KeyArena (formerly Washington State Pavilion, Washington State Coliseum and Seattle Center Coliseum) is a multi-purpose arena in Seattle.  It is located north of downtown in the 74 acre entertainment complex known as Seattle Center, the site of the 1962 World's Fair, the Century 21 Exposition.  It is used for entertainment purposes, such as concerts, ice shows, circuses, and sporting events.

UFC on Fox: Henderson vs. Diaz: UFC on Fox: Henderson vs. Diaz (also known as UFC on Fox 5) is a mixed martial arts event that was held by the Ultimate Fighting Championship on December 8, 2012, at KeyArena in Seattle, Washington.  It was broadcast live on Fox Sports.

Supporting paragraphs: UFC on Fox: Henderson vs. Diaz KeyArena
Answer: Washington