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': 'An ideal root-canal filling material should satisfy all of the following except which one? \nSelect and explain. \nA. The material should be well tolerated by periradicular tissues, B. The material should be easily placed, C. The material should be absorbable, D. The material should be visible radiographically', 'role': 'user'}, {'content': "Answer: C \nExplanation: Grossman's Requirements for an Ideal Root Canal Filling Material\xa0\n\nThe material should be easily introduced into the root canal.\nIt should seal the canal laterally as well as apically.\nIt should not shrink after being inserted.\nIt should set slowly.\nIt should be impervious to moisture.\nIt should be bactericidal or, at least, should discourage the growth of bacteria.\nIt should be radiopaque.\nIt should not stain the tooth structure.\nIt should not irritate periradicular tissues or affect the tooth structure.\nIt should be sterile, or easily and quickly sterilized immediately before insertion.\nIt should be easily removable from the root canal if necessary.\xa0\n\nRef: Grossman endodontics 13th ed page no 343", 'role': 'assistant'}]