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': "Which of the following factors in the stephan's curve is related to the caries incidence and sugar intake: \nSelect and explain. \nA. Physical form of sugar, B. Frequency of sugar intake, C. Ph of plaque, D. Quantity of sugar intake", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]