常見問題：
問：4. Q: What was Secret's debut song? 答： A: Secret's debut song was "I Want You Back," released in 2009.
問：8. Q: Has Secret appeared on any variety shows? 答： A: Yes, Secret has appeared on various South Korean variety shows, such as "Invincible Youth," "Law of the Jungle," and "Hello Baby."
問：全孝盛是誰？ 答：全孝盛是韓國女子團體Secret的成員之一。