This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Medicine
Acute metabolic acidosis: 
Select and explain. 
A. Has biphasic effect on K+ excretion, B. Does not effect K + excretion, C. Decreases urinary K+ excretion, D. Increase urinary K+ excretion
C: Decreases urinary K+ excretion
Answer: C: Decreases urinary K+ excretion 
Explanation: When H+ concentration is increased as in acidosis, H+ ions are secreted (preferentially over K+ ions) in exchange of Na+Thus in acidosis K+ secretion into tubules (excretion) is inhibitedRef: Harrison's 18/e p366