This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Radiological anatomy, Subject name: Radiology
[{'content': 'The arrow is located in which of the following structures? \nSelect and explain. \nA. Left costophrenic angle, B. Left cardiophrenic angle, C. Right costophrenic angle, D. Right cardiophrenic angle', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]