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': "A 60 year male presented with the feature of coloured halos was examined with fincham's test, which revealed that halos split and then reunion, Diagnosis is: \nSelect and explain. \nA. Acute congestive glaucoma, B. Open angle glaucoma, C. Senile immature cataract, D. Mucopurulant conjunctivitis", 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Senile immature cataract', 'role': 'assistant'}]