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': "Most common field defect in papillitis is \nSelect and explain. \nA. A relative central or centrocecal scotoma, B. Siedel's scotoma, C. Baring of blind spot, D. Tunnel vision", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most common field defect in optic neuritis is a relative central or centrocecal scotoma.', 'role': 'assistant'}]