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 impoant factor on which development of papilloedema depends in intracranial tumours is: \nSelect and explain. \nA. Site of tumour, B. Size of tumour, C. Nature of tumour, D. Rate of growth of tumour', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Site of tumour', 'role': 'assistant'}]