Question: A 35-year-old man is brought to the ED by his roommate after he was found lying unconscious in his apartment, which he heats with a wood-pellet stove. On examination, his Glasgow Coma Scale score is 4. He does not drink alcohol or abuse recreational drugs. Which of the following is a possible cause of his condition? Carbon monoxide poisoning Methanol poisoning Carbon dioxide poisoning Organophosphate poisoning COPD