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
Chance of subsequent baby having NTD when first baby was born with NTD - 
Select and explain. 
A. 2%, B. 4%, C. 10%, D. 20%
B: 4%
Answer: B: 4% 
Explanation: Ans. is 'b' i.e., 4%The recurrence risk of neural tube defect is :3 - 5 % if a couple has previously had a child with either anencephaly or spina bifida.5% if either parent was born with a NTD.10% if a couple has two affected children