Question: Which South Korean singer/actress was a member of both DIA and I.O.I?

full_context: Document 1: Ki Hui-hyeon: Ki Hui-hyeon (born June 16, 1995), better known by the mononym Huihyun and former stage name Cathy, is a South Korean singer. She is best known as a member of the South Korean girl group DIA.
Document 2: Pristin: Pristin (Hangul: 프리스틴 ; stylized as PRISTIN and formerly known as Pledis Girlz) is a South Korean girl group formed by Pledis Entertainment in 2016. The group is composed of ten members: Nayoung, Roa, Yuha, Eunwoo, Rena, Kyulkyung, Yehana, Sungyeon, Xiyeon and Kyla. Most of them appeared on the television show "Produce 101" and, as the prize for becoming two of the top contestants, Nayoung and Kyulkyung went on to debut as part of the project girl group I.O.I, before reuniting with the other members to debut as Pristin on March 21, 2017, with the first mini album "Hi! Pristin". Like their labelmate group Seventeen, Pristin is known for writing and composing their own music.
Document 3: Sixteen (TV series): Sixteen (, stylized as SIXTEEN) was a 2015 reality girl group survival show created by JYP Entertainment and Mnet. The show pitted sixteen JYP trainees against one another to secure a spot in the girl group Twice. "Sixteen" contestants were assessed for not only their singing and dancing abilities but also their charisma and personality. The show premiered on May 5, 2015, and ran for ten episodes through July 7, 2015, on Mnet.
Document 4: Twice (band): Twice (; Japanese: トゥワイス) is a South Korean girl group formed by JYP Entertainment through the 2015 reality show "Sixteen". The group is composed of nine members: Nayeon, Jeongyeon, Momo, Sana, Jihyo, Mina, Dahyun, Chaeyoung, and Tzuyu. The group debuted on October 20, 2015 with the extended play (EP) "The Story Begins".
Document 5: Exo (band): Exo (Korean: 엑소 ; stylized as EXO) is a South Korean-Chinese boy group based in Seoul. Formed by S.M. Entertainment in 2011, the group debuted in 2012 with twelve members separated into two subgroups, Exo-K (Suho, Baekhyun, Chanyeol, D.O., Kai, and Sehun) and Exo-M (Xiumin, Lay, Chen and former members Kris, Luhan and Tao ), performing music in Korean and Mandarin respectively. Exo's first album "XOXO" (2013), which contained the breakthrough hit "Growl", was a critical and commercial success, winning both Disk Daesang at the 28th Golden Disk Awards and Album of the Year at the 15th Mnet Asian Music Awards. It sold over one million copies, making Exo the best-selling Korean artist in twelve years. Subsequent albums and EPs continued with strong sales, and Exo were ranked the most influential celebrity by "Forbes" Korea Power Celebrity for the years 2014 and 2015. They have been named "the biggest boyband in the world" by media outlets.
Document 6: Wonder Girls: Wonder Girls () was a South Korean girl group and band formed by producer Park Jin-young under JYP Entertainment in 2006, which debuted in 2007. The group's final line-up consisted of Yubin, Yeeun, Sunmi and Hyerim. Members Sunye and Sohee officially left the group in 2015, while Hyuna left in late 2007. They were co-managed in the United States by Creative Artists Agency.
Document 7: I.O.I: I.O.I (; also known as IOI or Ideal of Idol) was a South Korean girl group formed by CJ E&M through the 2016 reality show "Produce 101" on Mnet. The group was composed of eleven members chosen from a pool of 101 trainees from various entertainment companies: Lim Na-young, Kim Chung-ha, Kim Se-jeong, Jung Chae-yeon, Zhou Jieqiong, Kim So-hye, Yu Yeon-jung, Choi Yoo-jung, Kang Mi-na, Kim Do-yeon and Jeon So-mi. They debuted on May 4, 2016 with the EP "Chrysalis" and actively promoted as a whole and as a sub-unit for less than a year.
Document 8: Jung Chae-yeon: Jung Chae-yeon (born December 1, 1997), better known by the mononym Chaeyeon, is a South Korean singer and actress. She is best known for being a member of the South Korean girl group DIA, and for finishing 7th in the survival show "Produce 101", making her a member of I.O.I.
Document 9: Dia (singer): Dia (Hangul: 디아, stylized as DIA) (born June 12, 1992) is a South Korean singer and a member of the disbanded girl group Kiss&Cry.
Document 10: Seo Yu-na: Seo Yu-na (born December 30, 1992), better known by the mononym Yuna, is a South Korean singer and actress. She is a member of the South Korean girl group AOA and its sub-groups, AOA Black and AOA Cream.
Document 11: Kim Chung-ha: Kim Chung-ha (born Kim Chan-mi on February 9, 1996), better known by the mononym Chungha, is a South Korean singer. She is best known for finishing fourth in Mnet's girl group survival show "Produce 101" and as a former member of the now disbanded South Korean girl group I.O.I.
Document 12: AOA (group): AOA (Hangul: 에이오에이 ; an acronym for Ace of Angels) is a South Korean idol girl group signed under FNC Entertainment. Initially, AOA debuted as an eight-member girlband that consisted of Choa, Jimin, Yuna, Youkyung, Chanmi, Hyejeong, Seol-hyun, and Mina. Currently, AOA is promoting as a six-member idol girl group following Choa's departure, and Youkyung, who was only a part of AOA Black. The group officially debuted by having their debut music stage on August 9, 2012, on M Countdown.
Document 13: Fromis: Fromis (; initialism for From Idol School; stylized as fromis_) is an upcoming South Korean girl group formed by CJ E&M through the 2017 reality show "Idol School" on Mnet. The group is composed of nine members: Roh Ji-sun, Song Ha-young, Lee Sae-rom, Lee Chae-young, Lee Na-gyung, Park Ji-won, Lee Seo-yeon, Baek Ji-heon and Jang Gyu-ri. The group's name, pronounced as "promise" in Korean, also means "to keep their promise [to viewers] to be the best girl group".
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: Chae Jung-an: Chae Jung-An (born Jang Jung-An on September 9, 1977) is a South Korean actress and singer.
ground_truth: Jung Chae-yeon