What girl group did a star of Defendant debut as a member of in 2007?
Defendant (TV series): Defendant () is a South Korean television series starring Ji Sung with Um Ki-joon, Kwon Yu-ri, Oh Chang-seok and Uhm Hyun-kyung. Kwon Yu-ri:  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.
Girls' Generation