This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Physiology
[{'content': 'Pancreatic juice becomes thick if it has impaired \nSelect and explain. \nA. Na secretion, B. Cl- secretion, C. Na+ H+ exchange, D. H+ secretion', 'role': 'user'}, {'content': 'Answer: B \nExplanation: As the volume of pancreatic secretion increases, its Cl- concentration falls and its HCO3- concentration increases.The magnitude of the exchange is inversely propoionate to the rate of flow.In cystic fibrosis where this exchange mechanism is lost, pancreatic secretions become dehydrated and thickenedREF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY, TWENTY-THIRD EDITION, PAGE NO:435,436', 'role': 'assistant'}]