A child has two favorite glasses: a tall, skinny one with a picture of a giraffe on it and a short, fat one with a picture of a hippopotamus on it. When her mother pours her some milk using the "hippo" glass, the girls asks that the milk be moved into the "giraffe" glass because she is really thirsty. If the girl believes that simply transferring the milk into the taller glass increases the amount, she probably
◦ is in the stage of formal operations.
◦ has not yet reached the concrete operational stage.
◦ is incapable of accommodation.
◦ is capable of mental operations.