This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumour markers, Subject name: Pathology
All of the following are examples of tumour markers, except: 
Select and explain. 
A. Alpha-HCG, B. AFP, C. NSE, D. CEA
A: Alpha-HCG
Answer: A: Alpha-HCG 
Explanation: Tumor markers Tumor Types Human chorionic gonadotropin Trophoblastic tumors, nonseminomatous testicular tumors a- Fetoprotein Liver cell cancer, nonseminomatous germ cell tumors of testis Carcinoembryonic antigen(CEA) Carcinomas of the colon, pancreas, lulng, stomach, and hea Neuron-specific enolase (NSE) Small-cell cancer of lung, neuroblastoma Alpha HCG is not a tumor marker