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
Twin peak sign seen in: 
Select and explain. 
A. Monochorionic diamniotic, B. Dichorionic monoamniotic, C. Conjoined twins, D. Diamniotic dichorionic
D: Diamniotic dichorionic
Answer: D: Diamniotic dichorionic 
Explanation: The twin peak sign is characteristic of dichorionic pregnancy and is due to chorionic tissue between the two layers of the ine twin membrane at the placental origin.In monochorionic twins there is no chorionic tissue giving rise to T sign on (refer pgno:180 sheila textbook of obstetrics 2nd edition)