A 63-year-old man with chronic kidney disease stage 3 (eGFR 42 mL/min/1.73 m²) presents to the emergency department with potassium of 6.8 mmol/L, ECG showing peaked T waves and widened QRS complexes. What is the most appropriate immediate treatment?AAdminister intravenous calcium gluconate and nebulised salbutamol, then insulin-dextrose infusionBGive oral sodium polystyrene sulfonate onlyCStart haemodialysis without temporising measuresDObserve and repeat potassium in 6 hoursEStop ACE inhibitor and review in a weekCheck my answer