This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Poisoning, Subject name: Anatomy
[{'content': 'All are cardiac poisons except \nSelect and explain. \nA. Opioids, B. Digitalis, C. Oleander, D. Odollum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Cardiac poisons Are digitalis, oleander, odollum, aconite, hydrocyanic acid, cleistanthus. Ref: FORENSIC MEDICINE AND TOXICOLOGY Dr PC IGNATIUS THIRD EDITION PAGE 399', 'role': 'assistant'}]