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': 'Surface hardness of gold foil during condensation \nSelect and explain. \nA. Always increases, B. Always decreases, C. Increased followed by a decrease, D. Not correlated', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]