Question: The three-member South Korean boy band, High4, released in 2014 a song they collaborated with which South Korean singer, songwriter and actress who signed with LOEN Entertainment in 2007?
Sentence (from "IU (singer)"): Her follow-up albums, "Growing Up" and "IU...IM", brought her mainstream success, but it was through "Good Day" (Korean: 좋은 날 ), the lead single from her 2010 album "Real", that she achieved national stardom.
Relevant evidence: No