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': 'What is primary G.P. point: \nSelect and explain. \nA. Master point, B. Paper point, C. Initial file taken for working length determination., D. None of the above.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The primary G.P. point used to seal the canal is called Master point or primary emulsion.', 'role': 'assistant'}]