The correct option is A Carbon monoxide
Carbon monoxide, a product of incomplete combustion is a highly toxic colorless, odorless, and tasteless gas. It has affinity for haemoglobin way more than oxygen does. When too much carbon monoxide is in the air, body replaces the oxygen in bloodstream with carbon monoxide causing blood poisoning. This can cause dizziness, vomiting, weakness and may even lead to coma or death.