Question: When did the group debut that Kang Sung-hoon is a part of?
Sentence (from "Sechs Kies"): Consisting of members Eun Ji-won, Lee Jai-jin, Kim Jae-duck, Kang Sung-hoon, Ko Ji-yong and Jang Su-won, the group debuted on April 15, 1997.
Relevant evidence: Yes