This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Gynaecology & Obstetrics
Percentage of women who deliver on the expected date of delivery is 
Select and explain. 
A. 4%, B. 15%, C. 35%, D. 70%
A: 4%
Answer: A: 4% 
Explanation: Based on Naegele&;s formula labor stas approximately onExpected date in 4%One week either side in 50%2 weeks earlier and 1 week later in 80%42 weeks in 10%43 plus weeks in 4%D.C.DUTTA&;S TEXTBOOK OF GYNECOLOGY, Pg no:113,7th edition