This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'Sensorimotor\tstage\tof\tcognitive\tdevelopment\tis\ncharacterized by \nSelect and explain. \nA. Egocentricism, B. Symbolic play, C. Animism, D. Conservation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]