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
In fetus the insulin secretion begins by: 
Select and explain. 
A. 3rd month, B. 5th month, C. 7th month, D. 7th month
A: 3rd month
Answer: A: 3rd month 
Explanation: A i.e. 3rd month