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: Surgery
Sentinel lymphnode is: 
Select and explain. 
A. Group of lymphnodes, B. First stop along the route of lymphatics, C. A node that is skipped during distant metastasis, D. Distant metastatic node
B: First stop along the route of lymphatics
Answer: B: First stop along the route of lymphatics 
Explanation: None