This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': 'Which of the following is antidote for beta-blocker poisoning? \nSelect and explain. \nA. Calcium gluconate, B. Glucagon, C. Sodium phosphate, D. Chloride salts', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Calcium gluconate is antidote for potassium and for MGSO4 Glucagon is used for beta-blocker poisoning which neutralizes bradycardia, hypotension by stimulating cyclic AMP. Ref : KAtzung 12th ed.', 'role': 'assistant'}]