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': 'Second sight phenomenon is seen in - \nSelect and explain. \nA. Nuclear cataract, B. Coical cataract, C. Senile cataract, D. Iridocyclitis', 'role': 'user'}, {'content': "Answer: A \nExplanation: In patients with nuclear sclerosis, distant vision deteriorates due to progressive index myopia. Such patients may be able to read without presbyopic glasses. This improvement in near vision is referred to as 'second sight'. REF IMG", 'role': 'assistant'}]