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': 'Which of the following statements is true regarding subclan steal syndrome? \nSelect and explain. \nA. Reversal of blood flow in the ipsilateral veebral aery, B. Reversal of blood flow in the contralateral carotid aery, C. Reversal of blood flow in the contralateral veebral aery, D. Bilateral reversal of blood flow in the veebral aeries', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Reversal of blood flow in the ipsilateral veebral aery', 'role': 'assistant'}]