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: Gynaecology & Obstetrics
Alpha-fetoprotein is increased in following except: 
Select and explain. 
A. Open neural tube defect, B. Down's syndrome, C. Oesophageal atresia, D. Exomphalos
B: Down's syndrome
Answer: B: Down's syndrome 
Explanation: Down's syndrome