This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Development of GU system and Neuro-vascular supply of pelvis & perineum, Subject name: Anatomy
When does the metanephros become functional? 
Select and explain. 
A. At week 3 of development, B. At week 4 of development, C. At week 10 -12 of development, D. Just before bih
C: At week 10 -12 of development
Answer: C: At week 10 -12 of development 
Explanation: The metanephros begins to form at week 5 and stas to function in the fetus at about week 10-12 The pronephros is not functional in humans. The mesonephros leaves behind mesonephric duct & gets degenerated.