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 narrow continuous line of brown dots which follow contour of gingival margin of posterior teeth in children is known as: \nSelect and explain. \nA. Burtonian line, B. Mesenteric line, C. Neonatal line, D. Developmental line', 'role': 'user'}, {'content': 'Answer: B \nExplanation: A black strain in the form of a fine line adjacent to the\xa0free gingival margin, which is not related to smoking, has been called metabolic strain and “mesenteric line.”\nThis stain may occur as a broad thin black line following the contour of the free gingival margin onto the\xa0interproximal surface of the teeth.', 'role': 'assistant'}]