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: Pharmacology
[{'content': 'An experimental drug is found to preferentially dilate autoregulatory coronary arterioles without affecting large conducting vessels. It is likely to: \nSelect and explain. \nA. Evoke coronary steal phenomenon, B. Mitigate classical angina but not variant angina, C. Produce tachycardia as an adverse effect, D. Useful in CHF', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]