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': "Rider's caramel is seen in - \nSelect and explain. \nA. Blue dot eataract, B. Zonular cataract, C. Anterior capsular cataract, D. Coronary cataract", 'role': 'user'}, {'content': 'Answer: B \nExplanation: In zonular cataract the main mass of the lens internal and external to the zone of cataract is clear, except for small linear opacities like spokes of a wheel (riders) which may be seen towards the equator.', 'role': 'assistant'}]