Question: What girl group did a star of Defendant debut as a member of in 2007?
Context: D.Holic (Hangul: 디홀릭) was a South Korean girl group formed by Star Road Entertainment (formerly H.Mate Entertainment) in 2014 with five members.  Nine left the group in August 2015, due to personal reasons, and was replaced by new member, Hwajung.  In July 2016, it was revealed through teasers that Danbee and Duri had decided to leave the group, new member, EJ, was added to the line-up.  In February 2017, it was confirmed through a performance that members Hami and Hwajung had departed from the group.  They were temporary replaced with new members, Nayoung and Youjin, although they never officially made their debut.  In July 2017, EJ announced that she would be leaving the group to pursue a modelling career.  The group informally disbanded after the departure of all but one member, with the aim of re-debuting the remaining member, Rena, into a new girl group within a year.  The group has released one mini-album: "Chewy" (2015) and three single albums: "D.Holic Dark With Dignity" (2014), "Murphy & Sally" (2015), and "Color Me Rad" (2016). Lee Hae-in (born July 4, 1994) is a South Korean singer and actress.  She debuted in project girl group I.B.I, a project girl group that consists of Produce 101 eliminated contestants formed by LOEN Entertainment, which debuted in August 2016.  In 2017, she joined another survival girl group show, Idol School as a contestant. Kim Hyun-ah (born June 6, 1992), better known by the mononym Hyuna, stylized as HyunA, is a South Korean singer, dancer, songwriter and model.  She rose to fame in the late 2000s as a member of the girl group Wonder Girls, leaving the ensemble shortly after their debut in 2007 and subsequently joining the girl group 4Minute in 2009.  Hyuna began a solo career in 2010, which she describes as "performance-oriented music".  Her debut single "Change" peaked at #2 on the Gaon Digital Chart. Muses Diary is the debut single album recorded by South Korean girl group Nine Muses A, a sub-group from girl group Nine Muses.  The single album was released as a digital download on August 4, 2016 by Star Empire Entertainment and distributed by KT Music, and as a physical album on August 8.  The title track is "Lip 2 Lip" and was written and composed by Jung Changwook.  The single has two B-sides, "Shh!"  and "Monster". Kwon Yu-ri (born December 5, 1989), better known by the mononym Yuri, is a South Korean singer and actress.  She debuted as a member of girl group Girls' Generation in August 2007, who went on to be one of the best-selling artists in South Korea and one of South Korea's most popular girl groups worldwide.  Apart from her group's activities, she has been in several television dramas such as "Fashion King" (2012), "Neighborhood Hero" (2016), the web drama "Gogh, The Starry Night" and "Defendant" (2017).  In 2013, she made her film debut in "No Breathing". The discography of British girl group Little Mix consists of four studio albums, seventeen singles and eighteen music videos. Having become the first ever group to win the show, winners of "The X Factor" Little Mix released their debut single "Cannonball" a cover of Damien Rice's single in December 2011.  The single became the group's first number-one single when it topped the UK Singles Chart.  The lead single from their debut album "Wings" became their second number one single in the UK.  It also reached number three in Australia and number 14 in the New Zealand.  In November 2012, Little Mix released their debut album "DNA".  The album peaked inside the top 10 in ten countries, including the UK where it debuted number three.  The album has been certified Platinum in the UK where it has sold 391,447 copies there as of April 2016.  In May 2013, the group released their debut album in the United States, where it debuted at number four, becoming the highest debut from a British girl group in the US, beating a record previously held by the Spice Girls, who debuted at number six with their debut album "Spice" in 1996.  "DNA" spawned three more singles; the top three hit and title track "DNA" and the top 20 singles "Change Your Life" and "How Ya Doin'? ". GP Basic (Korean: 지피 베이직 ) was a South Korean girl group who debuted on August 15, 2010.  At the time of their debut, they were considered to be the "youngest" South Korean girl group with an average age of below 13.5.  The age of their youngest member, Janey, caused controversy followed by the debut of a much younger girl group, G-story, who were all below 10 years old.  This led to new broadcasting regulations in South Korea. Defendant () is a South Korean television series starring Ji Sung with Um Ki-joon, Kwon Yu-ri, Oh Chang-seok and Uhm Hyun-kyung.  It aired on SBS from January 23 to March 21, 2017 on Mondays and Tuesdays at 22:00 (KST) for 18 episodes. Black Pearl (Hangul: 블랙펄) was a South Korean girl group official made up of Oh Nami, Hwl Eun, Young Joo, and Mikka.  When the group debuted in 2007 they marketed as the new girl group to dominate the girl group charts in the following years of 2007 and 2008 alongside some artist Wonder Girls, and Kara.  They were also known to follow the steps of SG Wannabe, SeeYa, and M2M.  In 2009 Mikka left due to personal reasons.  New member Jung Min was added by 2010 or 2011.  As for the 2010 and therefore the group only consisted of the following 4 until their disbandment in 2012. The Sugababes are an English girl group formed in 1998 by Siobhán Donaghy, Mutya Buena and Keisha Buchanan.  Their debut album, "One Touch", was released in the UK through London Records on 27 November 2000.  The album achieved moderate success, peaking at number 26 in April 2001 and eventually being certified Gold.  In 2001, Donaghy departed the group amid rumours of a rift with Buchanan and the group were dropped by their record label.  With the introduction of Heidi Range, former member of fellow English girl group Atomic Kitten, the group began to experience a higher level of commercial success whilst keeping the critical acclaim they had achieved with their debut album.  They released three studio albums before Buena announced her departure in December 2005, leading to Amelle Berrabah being brought in to replace her.  Following the release of their first greatest hits album, the new line-up released two studio albums.  In September 2009, after 11 years in the Sugababes, Buchanan, the final original member, was replaced by former UK Eurovision entry Jade Ewen.  Range, Berrabah and Ewen released the group's seventh studio album, "Sweet 7", in 2010, after which they signed to RCA Records, before announcing an indefinite hiatus in 2011.  In 2013, Ewen confessed that the Sugababes had split two years earlier.  The original line-up of the band reformed in 2011, under the new name Mutya Keisha Siobhan.
Answer: Girls' Generation