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': 'In a 10-year-old child the lower canines are trying to erupt in 2mm insufficient space. The primary molars are large and firmly fixed. The 1st premolars are also erupting. The treatment of choice is: \nSelect and explain. \nA. Remove primary 2nd molars, B. Place a removable bite-opener, C. Remove 1st premolars, D. Mesial stripping of primary 2nd molars', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]