This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diagnosis in Obstetrics, Subject name: Gynaecology & Obstetrics
A mother comes with history of antenatal fetal death due to neural tube defect in first child. What is the amount of folic acid you will prescribe during preconceptional counseling (in micrograms/day)? 
Select and explain. 
A. 4, B. 40, C. 400, D. 4000
D: 4000
Answer: D: 4000 
Explanation: Ans. is d, i.e. 4000Ref. Williams Obs 24/e, p 1104Folate Requirement in normal pregnancy: 4 microgramsFolate requirement in pregnancy with previous history of neural tube defects: 4 mg.