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': 'The most important factor on which development of papilloedema depends in intracranial tumour is \nSelect and explain. \nA. Site of tumour, B. Nature of tumour, C. Size of tumour, D. Rate of growth', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]