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: Physiology
α - intercalated cells are present in _________ helps in __________ 
Select and explain. 
A. Distal convoluted tubule, HCO3– secretion, B. Distal convoluted tubule, H+ secretion, C. Collecting duct, H+ secretion, D. Collecting duct, HCO3– secretion
C: Collecting duct, H+ secretion
Answer: C: Collecting duct, H+ secretion 
Explanation: Intercalated cells are present in Collecting duct
I cells are of 2 types.

Alpha : acid secretion
Beta : HCO3 secretion