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: Ophthalmology
[{'content': 'Macular differentiation occurs at the age of \nSelect and explain. \nA. 2 - 4 months, B. 6 - 8  months, C. 4 - 6 months, D. 5 - 7 years', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Macular differentiation occurs at the age of 4 - 6 months.', 'role': 'assistant'}]