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': 'Which one of the following does not commonly survive in a periapical lesion? \nSelect and explain. \nA. Pseudomonas, B. Streptococcus, C. Porphyromonas, D. Actinomyces', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]