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': 'In fetus the insulin secretion begins by: \nSelect and explain. \nA. 3rd month, B. 5th month, C. 7th month, D. 7th month', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. 3rd month', 'role': 'assistant'}]