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
Earliest tumor to appear after birth is 
Select and explain. 
A. Cystic hygroma, B. Lymphoma, C. Branchial cyst, D. Sternomastoid tumor
A: Cystic hygroma
Answer: A: Cystic hygroma 
Explanation: None