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: Surgery
Condition which does not cause metabolic acidosis? 
Select and explain. 
A. Renal failure, B. Ureterosigmoidostomy, C. Pancreatic or biliary fistula, D. Pyloric stenosis
D: Pyloric stenosis
Answer: D: Pyloric stenosis 
Explanation: Ans. is 'd' i.e., Pyloric stenosis