This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ectopic Pregnancy (Hello ! Where are you ?), Subject name: Gynaecology & Obstetrics
[{'content': 'Of the following potential clinical outcomes of tubal pregnancy, which one is the commonest? \nSelect and explain. \nA. Tubal rupture, B. Tubal aboion, C. Vascular insufficiency degenerating the embryo, D. Cornual pregnancy reaching term duration', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Most common termination of an ectopic is that the pregnancy outgrows the blood supply of the tube and eventual vascular insufficiency causes degeneration. Rupture of the tube is a rare outcome.', 'role': 'assistant'}]