This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
[{'content': 'Which of the following would be most likely causing methotrexate therapy failure in ectopic pregnancy treatment. \nSelect and explain. \nA. Multiparous woman, B. Ectopic size > 2.5 cm, C. Previous history of ectopic pregnancy, D. Serum β hcG level of 9000 mIU / mL.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: With methotrexate therapy, serum\xa0β-hcG levels should decline. If\xa0β-hcG rises then it is failure of medical management.', 'role': 'assistant'}]