Answer: two opposite sex adolescents occupying one room.
Step-by-step explanation:
A overcrowded room is a room that has fewer bedrooms for the occupants in the room which is typically based on the sex and age of the occupants.
Therefore, an overcrowded room is two opposite sex adolescents occupying one room. In this case, since they are opposite genders and are matured enough, they should not be staying in a room together but rather have their own separate rooms. Therefore, in this case, the room is overcrowded.