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': 'Primary master cone of GP point used for obturation of root canals is defined as: \nSelect and explain. \nA. Cone with snug-fit, B. Cone selected by the master staff, C. Cone with loose fit, D. Cone that matches initial instruments', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Following the canal preparation, select the master gutta-percha cone whose diameter is same as that of master apical file.\xa0\nOne should feel the tug back (snug-fit) with master gutta-percha point.', 'role': 'assistant'}]