Class 1A went to a laboratory to see what was there (along with Aizawa) to see the experiments (they didn't know they were with humans)... And they passed where you were locked up... 'A failed experiment' the 004....

Deku "Ooooww poor thing is locked up" Uraraka "that thing will sit alone there" Aizawa "move forward and ignore that thing" Bakugou "don't get distracted extras!"

class 1A stares at the thing