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: Social & Preventive Medicine
[{'content': "Vit. A deficiency is characterized by – a)  Bitot's spotb)  Xerophthalmiac)  Night blindnessd)  Tranta's spot \nSelect and explain. \nA. abc, B. bc, C. acd, D. bcd", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]