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: Pathology
[{'content': 'The carious lesion marked by the arrow represents: \nSelect and explain. \nA. Forward caries, B. Backward caries, C. Recurrent caries, D. Smooth surface caries', 'role': 'user'}, {'content': "Answer: C \nExplanation: Recurrent Caries:\nRecurrent caries is that type which occurs in the. It is usually due to inadequate extension of the original restoration, which favors retention of debris, or to poor adaptation of the filling material to the cavity, which produces a ‘leaky margin’.\xa0\nRef: Shafer's textbook of oral pathology 7th edition page 445", 'role': 'assistant'}]