This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
[{'content': 'The age at which a child can make a tower of 9 cubes and draw a circle is \nSelect and explain. \nA. 24 months, B. 30 months, C. 36 months, D. 42 months', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Key fine motor developmental milestones4mo - Bidextrous reach (reaching out for objects with both hands)6mo - Unidextrous reach (reaching out for objects with one hand); transfers objects9mo - Immature pincer grasp; probes with a forefinger12mo - Pincer grasp mature15mo- Imitates scribbling; tower of 2 blocks18 mo- Scribbles; tower of 3 blocks2 yr - Tower of 6 blocks; veical and circular stroke3 yr - Tower of 9 blocks; copies circle4 yr - Copies cross; bridge with blocks5 yr- Copies triangle; gate with blocks Ref:Ghai 8e pg:50', 'role': 'assistant'}]