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': 'Ring of fire on USG signifies? \nSelect and explain. \nA. H. mole, B. Ectopic pregnancy, C. PCOD, D. Aneuploidy', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is'b'i.e., Ectopic pregnancyThe ring of fire sign also known as ring of vascularity signifies a hypervascular lesion with peripheral vascularity on colour or pulsed doppler examination of the adnexa due to low impedance high diastolic flow.This sign can be seen inCorpusluteum cyst (more commonly)Ectopic pregnancy", 'role': 'assistant'}]