Question: In what division is Nicolas Dalby competing in, in the American mixed martial arts organization which features the top-ranked fighters of the sport?

Context paragraphs:
Shooto: Shooto is a combat sport/mixed martial arts system and mixed martial arts organization that is governed by the "Shooto Association" and the "International Shooto Commission".  Shooto was originally formed in 1985, as an organization and as a particular fighting system derived from shoot wrestling.  Practitioners are referred to as shooters, similarly to practitioners of shoot wrestling.  Shooto rules have evolved such that their events are now true mixed martial arts competitions.

KHK MMA: The Khalid Bin Hamad Al Khalifa Mixed Martial Arts (KHK MMA) is a martial arts organization based in Bahrain.  It was founded under the patronage of His Highness Khalid bin Hamad Al Khalifa for its current CEO and professional MMA fighter Mohammed "The Hawk" Shahid in February 2015.  Fighters competing under KHK MMA banner include: former UFC lightweight champion Frankie Edgar, UFC lightweight contender Khabib Nurmagomedov, UFC lightweight fighter Islam Makhachev, Bellator fighter James Gallagher, 2-time IMMAF champion Jose "Shorty" Torres, former UFC fighter and current Titan FC contender Alex Soto, and current Desert Force fighter Hamza Kooheji.  KHK MMA activities include: coaching pro fighters, developing amateur MMA, promoting martial arts events, fitness gyms, and a sports gear brand.

Alliance MMA: Alliance MMA, Inc. (NASDAQ: AMMA) is a mixed martial arts organization offering premier promotional opportunities for aspiring mixed martial arts (MMA) fighters to showcase their talent and advance to the sport's highest level of professional competition.  Alliance MMA's mission is to identify and develop the next generation of Ultimate Fighting Championship (UFC) and other leading MMA promotion champions including The World Series of Fighting and Bellator.

ShoMMA: ShoMMA: Strikeforce Challengers was a mixed martial arts series produced by the mixed martial arts organization Strikeforce and the Showtime cable network.  Similar to Showtime's earlier "ShoXC", the purpose of the series was to highlight up and coming MMA fighters.

World Extreme Fighting: World Extreme Fighting (WEF) is the second longest continuously running mixed martial arts (MMA) promoter in the world.  It has hosted many top-ranked fighters in the 46 events produced since it began in 1997.  WEF was founded by Jamie Levine, a mixed martial artist with a 4-0 record, who once held the WEF Light Heavyweight belt.  Following on a resurgence plan constructed by private investors led by Eric B. Delisle in September, 2010, WEF began producing events that were broadcast on the Fox Sports Network.

Desert Force Championship: Desert Force Championship (DFC) is the largest mixed martial arts promotion company in the Arab World, which hosts most of the top-ranked Arab MMA fighters in the region.  The championship has held ten televised events and presided over approximately 100 matches.  DFC currently airs on MBC Action on a bi-monthly basis.  In 2010 Desert Force launched the “Elimination Series”, a single-elimination tournament for Arab MMA fighters competing to become the first regional MMA title belt holders in 7 respective weight classes.  Fighters from across the Middle East have competed in 7 weight classes, namely Bantamweights, Featherweights, Lightweights, Welterweights, Middleweights, Light-Heavyweights and Heavyweights; each class enforcing the Unified Rules of Mixed Martial Arts.  Participating countries include: KSA, United Arab Emirates, Qatar, Kuwait, Jordan, Iraq, Bahrain, Palestine, Syria, Lebanon, Egypt, Morocco, Tunisia.  In recent years DFC fights have been officially refereed by MMA referee Yves Lavigne.

Ultimate Fighting Championship: The Ultimate Fighting Championship (UFC) is an American mixed martial arts organization based in Las Vegas, Nevada, that is owned and operated by parent company WME–IMG.  It is the largest MMA promotion in the world and features the top-ranked fighters of the sport.  Based in the United States, the UFC produces events worldwide that showcase eleven weight divisions and abide by the Unified Rules of Mixed Martial Arts.  As of 2017, the UFC has held over 400 events.  Dana White serves as the president of the UFC.  He has held that position since 2001; while under the leadership of Dana White the UFC has grown into a globally popular multibillion-dollar enterprise.

Nicolas Dalby: Nicolas Dalby (born November 16, 1984) is a Danish mixed martial artist, competing in the welterweight division of the Ultimate Fighting Championship.

Warrior Xtreme Cagefighting: The Warrior Xtreme Cagefighting (WXC) is the largest mixed martial arts (MMA) promotion company in Michigan that hosts most of the top-ranked fighters in the state and is looking in 2017 to produce events Nationwide.  Based in the United States, the WXC has eight weight divisions and enforces the Unified Rules of Mixed Martial Arts.  Norbert Pasztor serves as the president of the WXC.

Respect Fighting Championship: Respect Fighting Championship (RESPECT.FC) is a mixed martial arts organization in Germany.  It has won the GNP Award for the best German promotion in 2009, 2010 and 2011 Especially noteworthy in this context is that RESPECT.FC has beaten the Ultimate Fighting Championship (the biggest mixed martial arts organization in the world), who was nominated with their first German based event UFC 99.  The events are broadcast by Fightcast.tv, the only HD Fightsport portal in Europe.

Supporting paragraphs: Nicolas Dalby Ultimate Fighting Championship
Answer: welterweight division