This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urethra & Penis, Subject name: Surgery
Which electrolyte abnormality occurs after TRUP: 
Select and explain. 
A. Hypokalemia, B. Hyponatremia, C. Hyperkalemia, D. Hypernatremia
B: Hyponatremia
Answer: B: Hyponatremia 
Explanation: Ans. (b) HyponatremiaRef: Bailey 26th Edition, page 1349* Most common electrolyte abnormality during TURP is HYPONATREMIA due to water intoxication.