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: Dental
[{'content': '2/3rd of the root completion is seen in an IOPA, which Nolla’s stage does this ﬁnding  corresponds with? \nSelect and explain. \nA. Stage 7, B. Stage 8, C. Stage 9, D. Stage 10', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]