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': 'True about mounting stones is \nSelect and explain. \nA. Fast setting, B. High expansion, C. High strength, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The use of an articulator makes it necessary to mount the casts using a gypsum-producing product. These materials are referred to as "mounting" stones or plasters. They are fast setting and have low setting expansion. The mounting plaster has a sufficiently low strength to permit easy trimming and facilitate separating the cast from the articulator mounting plates.\nPhillips Science of Dental Materials ed 12 pg 191', 'role': 'assistant'}]