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: Pharmacology
[{'content': 'Coicosteroid with maximum sodium retaining potential is: \nSelect and explain. \nA. Hydrocoisone, B. Prednisolone, C. Fludrocoisone, D. Deoxycoicosterone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Fludrocoisone', 'role': 'assistant'}]