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': 'Fixation reflex of eyes develop at \nSelect and explain. \nA. 2 - 4 months, B. 4 - 5 months, C. 9 months, D. 6 - 8 months', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Fixation reflex of eyes develop at 2 - 4\xa0months.', 'role': 'assistant'}]