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': 'Minimum vision loss is seen in which cataract? \nSelect and explain. \nA. Blue dot, B. Zonular, C. Anterior polar, D. Posterior polar', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Blue dot cataract: It is also called cataracta punctata-caerulea. It usually forms in the first two decades of life. The characteristic punctate opacities are in the form of rounded bluish dots situated in the peripheral pa of an adolescent nucleus and deeper layer of the coex. Opacities are usually stationary and do not affect vision. However, large punctate opacities associated with coronary cataract may marginally reduce the vision.Ref. Khurana; 4th edition; Pg. 173', 'role': 'assistant'}]