On April 21, 'Produce 101' season 2 trainees' rehearsal for 'M Countdown' was aired.
The trainees entered the studio in an orderly fashion by their ranks. Rank A dressed in light pink entered first, followed by B, C, D, and F. The trainees' position on the stage also depended on their ranks. Rank A took the center while rank F were placed on the floor; off the stage.
SEE ALSO: [SPOILER] Which trainee jumped from rank F to rank A on this week's 'Produce 101' season 2?
Lee Min Ki (Ren), who's a member of NU'EST, were unable to control his emotions and shed tears during rehearsal. Several other rank F trainees also showed tears as they were not able to step on stage at all.