Now, on December 17, agency MBK Entertainment's CEO Kim Kwang Soo stated, "Dia members Chaeyeon and Cathy have decided to leave the group in order to try out for 'Produce 101.'  We ask for a lot of support for Chaeyeon and Cathy, who are going on a new path.  Dia plans to now promote as five members rather than seven."

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The program the two girls will be trying out for is 'Produce 101,' a new Mnet survival series that takes trainees from different agencies and have them compete to debut as a project group.  It's interesting that idols who already debuted left to become trainees again in order to try out for a new group!  

The two of them wrote via Facebook, "We ask for a lot of interest and support in our new challenge.  Please be careful of the cold in the remarkable cold."  Good luck to you, girls!