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: Radiology
[{'content': 'A low kilovoltage technique is most advantageous in\ndemonstrating \nSelect and explain. \nA. Resorption of alveolar crest, B. Periapical lesions, C. Incipient caries, D. Nutrient canals', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]