This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Death and postmortem changes, Subject name: Forensic Medicine
[{'content': 'Cherry red colour of blood is seen in poisoning with \nSelect and explain. \nA. Nitrate, B. Cyanide, C. Lead, D. Sulphite', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Colour of death by poisoning: Cyanide- bright red Carbon monoxide - cherry red Carbon dioxide- deep blue Phosphorus, copper- dark brown Hydrogen sulphide- bluish green Opiates- black Nitrite, aniline, potassium chlorate, nitrobenzene, potassium bicarbonate- chocolate brown or coffee brown. Ref: FORENSIC MEDICINE AND TOXICOLOGY DR P C IGNATIUS THIRD EDITION PAGE 24', 'role': 'assistant'}]