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': 'Which of the following is true about vasa pre except? \nSelect and explain. \nA. Incidence is 1:1500, B. Moality rate of 20% with undiagnosed case, C. Associated with low lying placenta, D. Cesarean section is indicated', 'role': 'user'}, {'content': 'Answer: B \nExplanation: When the fetal vessels in the membrane cross the region of internal os and are ahead of the presenting pa,the condition is called vasa prae.An Apt test or Singer&;s alkali denaturation test can be performed to confirm a fetal bleed and thereby vasa prae (refer pgno:138 sheila textbook of obstetrics 2 nd edition)', 'role': 'assistant'}]