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': 'Which of the following statements is true regarding the choice between doing a composite or amalgam restoration? \nSelect and explain. \nA. Establishing restored proximal contacts is easier with composite., B. The amalgam is more difficult and techniquesensitive., C. The composite generally uses a more conservative tooth/cavity preparation., D. None', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The restoration of a proximal contact is easier with amalgam than composite. Amalgam is easier to use and is less technique-sensitive. Either material can be used for Class II restorations. Because an amalgam restoration requires a tooth preparation that has\n\na specified depth (for strength of the amalgam),\ncavosurface marginal configurations that result in 90-degree amalgam margins, and\nndercut form to its walls or secondary retention form features, they require more tooth structure removal than do composite tooth preparations.\n\nComposite tooth preparations require\n\nremoval of the fault, defect, or old material;\nremoval of friable tooth structure; and\nno specific depths—they are more conservative.', 'role': 'assistant'}]