<span>I believe the correct answer is Sobechi, who can
follow the rules of a game.</span>
Jean Piaget considered the stage of concrete
operations, third stage of cognitive development, as a major turning point in
the child's cognitive development. In this stage child learns think logically
and understands the concept of hierarchy. Therefore, Sobechi, who can follow
the rules of a game has entered the stage of concrete operation as he can now
think logically and understands that there are rules and hierarchy.