Question: Which singer is from South Korea, Anette Olzon or Park Gyu-ri?

full_context: Document 1: Nightwish discography: The discography of the Finnish symphonic metal band Nightwish consists of eight studio albums, one extended play, four live albums, seven compilations, thirteen music videos and twenty one singles. The band was formed in 1996 by songwriter and keyboardist Tuomas Holopainen, guitarist Emppu Vuorinen, and former vocalist Tarja Turunen; Nightwish's current line-up has six members although Turunen has been replaced by Anette Olzon, and the original bassist, Sami Vänskä, has been replaced by Marco Hietala, who also took over the male vocalist part. Olzon left the band in 2012 and was replaced by Floor Jansen.
Document 2: Kara (South Korean band): Kara (Hangul: 카라, Japanese: カラ, often stylized as KARA) was a South Korean pop girl group formed by DSP Media in 2007. The group's final lineup was composed of Park Gyuri, Han Seungyeon, Goo Hara and Heo Youngji. Members Nicole Jung and Kang Ji-young officially departed from the group in 2014, while Kim Sung-hee left in 2008. The group's name comes from the Greek word "chara" (χαρά, lit. "joy"), which they interpreted to mean "sweet melody".
Document 3: Anette Olzon: Anette Ingegerd Olsson (born 21 June 1971), known by the stage name Anette Olzon, is a Swedish singer, best known as the lead vocalist of Finnish symphonic metal band Nightwish from 2007 to 2012. She is also the former vocalist of Swedish classic rock band Alyson Avenue.
Document 4: Lee Hyori: Lee Hyo-ri (born May 10, 1979), is a South Korean singer, record producer, activist, actress and television presenter. Dubbed as the "Nation's Fairy" during her "Family Outing" days, she debuted as a member of South Korean girl group Fin.K.L, but has since become a solo artist. In 2003, she released her debut solo album "Stylish" which won several "Artist of the Year" awards. In 2006, Lee was the highest-paid female singer in South Korea when she signed a contract with Mnet Media.
Document 5: Changes (Alyson Avenue album): Changes is the third album by Swedish AOR/rock band Alyson Avenue with new vocalist Arabella Vitanc. Alyson Avenue released their third album "Changes" through Avenue of Allies. The record was co-produced by band members and Chris Laney (Crazy Lixx, H.E.A.T., Brian Robertson) and includes guest appearances by Anette Olzon (Ex-Nightwish, Ex-Alyson Avenue), Michael Bormann (Ex-Jaded Heart, Charade, BISS), Rob Marcello (Danger Danger, Marcello - Vestry), Fredrik Bergh, (Street Talk, Bloodbound), Tommy Stråhle and Mike Andersson (Cloudscape, Planet Alliance).
Document 6: Omega (Alyson Avenue album): Omega is the second studio album by Alyson Avenue, and the band's final album with lead vocalist Anette Olzon. It was released on May 6, 2004, by the label AOR Heaven. It was re-released on July 14, 2009, along with their first album "Presence of Mind". Omega II comes with five exclusive bonus tracks with Anette Olzon, and their first single "I Am (Your Pleasuremaker)".
Document 7: Nam Gyu-ri: Nam Gyu-ri (; born on April 26, 1985 in Seoul, South Korea) is a South Korean singer and actress. She was a former member and leader of the Korean female trio, SeeYa. In 2009, Nam Gyu-ri had a contract dispute with the group's management company and left the group. Nam has also acted, most notably in the film "Death Bell" and the drama "49 Days". In 2012, she was ranked at #58 on "The 23rd Annual Independent Critics List of the 100 Most Beautiful Faces".
Document 8: Eva (Nightwish song): "Eva " is the first single of Finnish symphonic metal band Nightwish's sixth studio album "Dark Passion Play". It was the first release to feature the band's new singer, Anette Olzon, following Tarja Turunen's departure in 2005.
Document 9: Shine (Anette Olzon album): Shine is the debut solo album by Swedish singer Anette Olzon, released on 26 March (Sweden), 28 March (Germany, Finland, Russia, Spain), 31 March (France, the Netherlands, Belgium, Luxembourg, Poland, Czech Republic, Norway, Denmark, the UK), 1 April (Italy), and 8 April 2014 (USA) by earMUSIC.
Document 10: Dark Passion Play World Tour: Dark Passion Play World Tour was the fourth world tour by Finnish symphonic metal band Nightwish, taking place from 2007 to 2009 in support of their sixth studio album, "Dark Passion Play", released by Nuclear Blast on September 26, 2007; it was the first tour with former frontwoman Anette Olzon, who joined the band in 2006, after Tarja Turunen's dismissal on October 21, 2005. During this tour, the band played for the first time in Israel, China, Hong Kong, Lithuania, Luxembourg, Republic of Ireland, Serbia and Croatia.
Document 11: List of Dark Passion Play editions: Dark Passion Play is the sixth studio album by Finnish symphonic power metal quintet Nightwish, released on September 26, 2007 in Finland, September 28 in Europe and October 2, 2007 in the United States. It was the first Nightwish album with the band's new lead singer, Anette Olzon, and the first album not featuring former vocalist Tarja Turunen, who was dismissed in October 2005. Lead songwriter Tuomas Holopainen has referred to it as the 'album that saved his life'.
Document 12: Han Seung-yeon: Han Seung-yeon (born July 24, 1988), better known mononymously as Seungyeon, is a South Korean singer and actress. She is best known as former main vocalist of the South Korean girl group Kara.
Document 13: Park Gyu-ri: Park Gyu-ri (born May 21, 1988), better known by the mononym Gyuri, is a South Korean singer, actress, and radio personality. She was a member of South Korean girl group Kara.
Document 14: Im Yoon-ah: Im Yoon-ah (Hangul: 임윤아 ; born May 30, 1990), better known by the mononym Yoona, is a South Korean singer and actress. She debuted as a member of girl group Girls' Generation in August 2007, who went on to become one of the best-selling artists in South Korea and one of South Korea's most popular girl groups worldwide.
Document 15: Park Geun-hye: Park Geun-hye (Hangul: 박근혜 ; Hanja: 朴槿惠 ; RR: "Bak Geun(-)hye " ; ] ; ; born 2 February 1952) is a former South Korean politician who served as President of South Korea from 2013 to 2017.
ground_truth: Park Gyu-ri