This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney, Subject name: Medicine
[{'content': 'Clinical feature of CRF - \nSelect and explain. \nA. Broad cast in urine, B. Hypomagnesemia, C. Hypokalemia, D. Impotence', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In chronic renal diseases, Degenerated cellular casts called waxy casts or broad casts(arising in the dilated tubules that have undergone compensatory hyperophy in response to reduced renal mass) may be seen in urine. Ref:Harrison 20th edition pg no. 294', 'role': 'assistant'}]