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: Radiology
[{'content': 'Ectopic pregnancy can be ruled out on ultrasound by: \nSelect and explain. \nA. Finding foetus in uterus, B. Normal adenexa, C. Uterus size propoional to foetal size, D. Clinical examination', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Finding foetus in uterus', 'role': 'assistant'}]