Conversation so far:
What was the line up changes South Korean group Kara faced?
South Korean group Kara Members Nicole Jung and Kang Ji-young officially departed from the group in 2014, while Kim Sung-hee left in 2008.
Why did Kang Ji-young leave the group Kara?
Kang Ji-young left South Korean group Kara because her contract was expiring and to puruse her other dreams.
Who was Kang Ji-young eplaced with?
South Korean group Kara member Kang Ji-young was replaced with Youngji.
What were the names of the two new members of Kara?
The two new members of South Korean group Kara are Younji and Hara.
What is Rock U by Kara?
Rock U is the first mini-album by South Korean girl group Kara.
How did the album Rock U by Kara do on the charts?
South Korean group Kara's album Rock U was in the Japan Oricon Weekly albums at 106.
Are there any other interesting aspects about the South Korean group Kara album Rock U besides being in the Japan Oricon Weekly albums at 106?
South Korean group Kara's album Rock U was also the first album to feature the two new members of the group; Kang Jiyoung and Goo Hara.
Did the South Korean group Kara tour at all?
South Korean group Kara's first concert tour was Karasia in 2012, as well as their second, third and fourth tour also titled Karasia in 2013, 2014 and 2015.
What career break though did Kara have?
South Korean group Kara Member Park Gyuri attributed their popularity increase to their pretty but natural appeal.

Question: What is their most recent single released?
Self-contained rewrite: What is Kara's most recent single released?