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: Physiology
[{'content': 'In the human kidney, a renal papilla projects directly into the: \nSelect and explain. \nA. Ureter, B. Major calyx, C. Minor calyx, D. Renal pyramid', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]