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': 'The principal disadvantage of metal denture base is \nSelect and explain. \nA. increase in weight, B. acrylic resin does not providing bonding, C. injure the soft tissues, D. it is difficult to reline', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]