This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Physiology
[{'content': 'Coronaryblood flow is increased by all of the following except \nSelect and explain. \nA. Beta adrenergic blockade, B. A decrease in aerial po2, C. An increase in aerial pCO2, D. Vagal stimulation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Beta adrenergic receptors causes karana vasodilation to increase CBF Blockage of these receptors causes decrease in the CBF Ref: page no 366 Textbook of physiology Volume 1 AK Jain 7th edition', 'role': 'assistant'}]