I.O.I (Hangul: 아이오아이; 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, Yoo 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.