Cha Soo Ah, formerly known professionally as I and Cha Yoon Ji, is a South Korean singer. She graduated from Seoul Performing Arts High School. She is the younger sister of former B1A4 member and current actor Cha Sun Woo (formerly known professionally as Baro).

She made her debut in January 2017 (using the stage name I) with her first mini-album, "I Dream", and managed by WM Entertainment (WM엔터테인먼트).

She later participated in the survival show "The Unit" but was eliminated in the earlier rounds. After the show's conclusion, she terminated her contract with WM Entertainment and became an independent singer in October 2018 and began using the stage name Cha Yoon Ji.

In mid-2019, she opened her YouTube account but after only 3 videos it was deleted. She went back to her birth name at some point in mid-2020 but, she is out of the entertainment industry since then.

(Source: MyDramaList) Edit Biography