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
Schwann cells are derived from: 
Select and explain. 
A. Neural crest cells, B. Endoderm, C. Mesoderm, D. Ectoderm
A: Neural crest cells
Answer: A: Neural crest cells 
Explanation: None