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: Anatomy
How many lactiferous ducts open in nipple ? 
Select and explain. 
A. 0 -10, B. 15 -20, C. 25 -50, D. 50 -75
B: 15 -20
Answer: B: 15 -20 
Explanation: The nipple is pierced by 15-20 lectiferous ducts.