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': "Chocolate cyanosis seen in \nSelect and explain. \nA. Wilson's disease, B. Zinc poisoning, C. Methemoglobinemia, D. Mercurialentis", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Methemoglobinemia Signs and symptoms Headache, nausea, vomiting, breathlessness, confusion, coma, convulsion, severe metabolic acidosis. Hemolysis may occur in G6PD deficiency. Blood is chocolate brown in color (chocolate cyanosis) Ref: FORENSIC MEDICINE AND Toxicology Dr PC IGNATIUS THIRD EDITION PAGE 430', 'role': 'assistant'}]