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
[{'content': 'Maximum contraction of gall bladder is seen with: \nSelect and explain. \nA. CCK, B. Secretin, C. Gastrin, D. Enterogastrone', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. CCK Most potent stimulus for causing gall bladder contraction is CCK-PZQ.', 'role': 'assistant'}]