This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lens, Subject name: Ophthalmology
[{'content': 'Polychromatic lusture is seen in- \nSelect and explain. \nA. Complicated cataract, B. Diabetes mellitus, C. Post radiation cataract, D. Congenital cataract', 'role': 'user'}, {'content': "Answer: A \nExplanation: In complicated cataract 'polychromatic luster'ie., appearance of iridescent coloured paicles of reds, greens and blue is a very characteristic sign (Rainbow cataract). IMG REF", 'role': 'assistant'}]