Fact 1: Carbon monoxide is a gas produced by furnaces and other devices that burn fuel. Fact 2: Carbon Monoxide Carbon monoxide is a health hazard. Given the two facts above, what are the affects of burning fuel on human health?

pick from the following. [i] emissions; [ii] They aid lung health.; [iii] direct damage to the lungs; [iv] They are a hazard.; [v] The affects are mildly healthy; [vi] The fuel burns clean.; [vii] Greenhouse gases; [viii] Global warming;
Answer:
[iv]