This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous System, Subject name: Pediatrics
[{'content': 'A case of meningomyelocele was posted for surgery. Till the patient is waiting for surgery, the covering of the sac will be protected by a gauze soaked in: \nSelect and explain. \nA. Normal saline, B. Tincture iodine, C. Methylene blue, D. Mercurochrome', 'role': 'user'}, {'content': "Answer: A \nExplanation: a. Normal saline(Ref: Nelson's 20/e p 2802-2803, Ghai 8/e p 575-577)Meningomyelocele is covered with sterile saline-soaked gauze to prevent it from drying, trauma and infection", 'role': 'assistant'}]