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': "Singer's alkali denaturation test is used to differentiate \nSelect and explain. \nA. Aboion from early pregnancy, B. Perimenopausal from pregnancy, C. Uterine malignancy from pegnancy, D. Vasa pre from placenta pre", 'role': 'user'}, {'content': "Answer: D \nExplanation: Singer's alkali denaturation test : It is a diagnostic test for vasa pre In this nucleated red blood cells are detected Ref: Dutta Obs 9e pg 243.", 'role': 'assistant'}]