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': "Salmon patch resolves after \nSelect and explain. \nA. 1 year, B. 3 years, C. 5 years, D. Doesn't resolve at all", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Salmon patch usually resolves after 1 year.', 'role': 'assistant'}]