This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid and electrolytes, Subject name: Medicine
Persistant vomiting most likely causes- 
Select and explain. 
A. Hyperkalemia, B. Acidic urine excretion, C. Hypochloraemia, D. Hyperventilation.
B: Acidic urine excretion
Answer: B: Acidic urine excretion 
Explanation: Metabolic alkalosis occurs as a result of loss of nonvolatile acid HCl while vomiting( from the extracellular fluid. 