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
A positive "Stallwohy&;s sign" is suggestive of which of the following conditions: 
Select and explain. 
A. Twin pregnancy, B. Breech presentation, C. Vesicular mole, D. Low lying placenta
D: Low lying placenta
Answer: D: Low lying placenta 
Explanation: If the earlier scan showed placenta completely over the internal os it is most likely to persist in the later scans.If the 18 -20 weeks scan revealed a low lying placenta or marginal placenta prae,placental localization is best repeated around 32 weeks (refer pgno:130 sheila textbook of obstetrics 2 nd edition)