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: Unknown
[{'content': 'Young lady presents with acute abdominal pain and history of 1 1/2 months amenorrhoea on USG examination there is a collection of fluid in the pouch of Douglas and empty uterine cavity. Diagnosis is \nSelect and explain. \nA. Ectopic pregnancy, B. Pelvic hematocele, C. Threatened abortion, D. Twisted ovarian cyst', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans-A ectopic pregnancy (Ref Dutta, 6/e, p 186 (5/e, p. 198, 4/e, pl98)).History of amenorrhoea and absence of gestational sac and collection of fluid in the pouch of Douglas leaves no doubt about the diagnosis of ectopic pregnancy.', 'role': 'assistant'}]