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 patient with visual acuity of <6/60 in better eye but more than 3/60 is having: \nSelect and explain. \nA. Economical blindness, B. Social blindness, C. Legal blindness, D. Absolute blindness', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Definitions of blindness: WHO definition of blindness: "Visual acuity of less than 3/60 (Snellen) or its equivalent". Economical blindness: Vision in better eye <6/60 to 3/60 Social blindness: Vision in better eye <3/60 to 1/60 Legal blindness: Vision in better eye <1/60 to perception of light Absolute/total blindness: No light perception Ref: Ophthalmology By A. K. Khurana, 3rd edition, Page 443, 444.', 'role': 'assistant'}]