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
[{'content': 'Pseudo gestational sac is seen in the USG of \nSelect and explain. \nA. Missed aboion, B. Ectopic gestation, C. Complete aboion, D. Hematometra', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pseudo gestational sac : Irregular in outline Usually, uterus is centrally located No double decidual sign Sac remains empty Seen in ectopic pregnancy Ref: Dutta Obs 9e pg 601.', 'role': 'assistant'}]