This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Malnutrition, Subject name: Pediatrics
[{'content': 'First clinical sign of vitamin A deficiency: \nSelect and explain. \nA. Poor growth, B. Conjunctival xerosis, C. Hydrocephalus, D. Phrynoderma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: First clinical sign of vitamin A deficiency is conjunctival xerosis, while 1st symptom is night blindness.', 'role': 'assistant'}]