This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Stroke and TIA, Subject name: Medicine
[{'content': 'Paradoxical embolism is detected by? \nSelect and explain. \nA. MRI Chest, B. Bubble contrast Echocardiography, C. CT scan Chest, D. Impedance plethysmography', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Paradoxical embolism Condition where a clot from venous return enters into the left atrium and left ventricle. Hencefoh, it can travel to the brain leading to cryptogenic stroke. Have a patent foramen ovale which allows transit of clot(s) in this fashion. Dx- Bubble contrast echocardiography is performed.', 'role': 'assistant'}]