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': 'Surinder singh developed acute CHF and was put on digitalis therapy. ECG of this patient revealed the presence of ventricular extrasystoles. Which of the following drugs can be administered safely to this patient in order to counteract this arrhythmia ? \nSelect and explain. \nA. Lignocaine, B. Quinidine, C. Atropine, D. Amiodarone', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]