This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth, Development, and Behavior, Subject name: Pediatrics
[{'content': 'The milestones of a 3-year-old child are considered delayed if he is unable to: \nSelect and explain. \nA. Hop on 1 foot, B. Use spoon effectively, C. Copy a square, D. Reliably catch a ball', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. Use spoon effectively(Ref: Nelson's 20/e p 75)Hop on 1 foot, copying a square & catching a ball reliably, comes at 48 m (4 yrs)A child is able to feed self at 18 months, but handles spoon effectively at 24 months (2 yrs)", 'role': 'assistant'}]