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
Widened anionic gap is not seen in : 
Select and explain. 
A. Acute renal failure, B. Diarrhea, C. Lactic acidosis, D. Diabetic ketoacidosis
B: Diarrhea
Answer: B: Diarrhea 
Explanation: Answer is B (Diarrhea) Diarrhea is a cause of normal anion gap metabolic acidosis produced as a result of increased gastrointestinal bicarbonate loss. The differential diagnosis of normal anion gap acidosis : Hyperalimentation Acetazolamide and other carbonic anhydrase inhibitors Renal tubular acidosis Diarrhea: due to a loss of bicarbonate. Ureteroenteric fistula Pancreaticoduodenal fistula Spironolactone The causes of High Anion Gap Acidosis: Lactic acidosis Ketoacidosis Diabetic ketoacidosis Alcohol abuse Toxins: Methanol Ethylene glycol Propylene glycol Lactic acid Uremia Aspirin Iron Isoniazid Cyanide, coupled with elevated venous oxygenation Renal failure