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: Medicine
[{'content': "Spironolactone is most useful in _________ syndrome: \nSelect and explain. \nA. Zollinger-Ellison, B. Conn's syndrome, C. Cushing syndrome, D. Acromegaly", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]