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': 'Intrinsic factor, which helps in absorption of Vit. B12 is produced by: \nSelect and explain. \nA. Parietal cells of stomach, B. Chief cells of stomach, C. Beta cells of pancreas, D. Goblet cells', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]