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': 'A coronally positioned pedicle graft is used when a single tooth exhibits gingival recession and \nSelect and explain. \nA. Bleeding, B. Pus discharge, C. Irreversible pulpitis, D. Sensitivity', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]