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: Medicine
[{'content': "1% w/v of methylene blue is injected intravenously into the tissue to reverse the toxic effects of \nSelect and explain. \nA. Methaemoglobinemia, B. Oxygen toxicity, C. Crohn's disease, D. Lidocaine toxicity", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]