Why do children in the preoperational stage fail at conservation tasks? O They are only capable of thinking about one physical dimension at a time. O They are only capable of thinking about two...

Extracted text: Why do children in the preoperational stage fail at conservation tasks? O They are only capable of thinking about one physical dimension at a time. O They are only capable of thinking about two physical dimensions simultaneously O Their developing visual systems cannot yet make precise judgments O Their short-term memory is unable to hold the required information all at once