It is cheaper than anything else. But that nuclear plant could explode etc. what I'm trying to say with the last part is that there is Good and Bad. I hope this helped.
D and A seem like good answers. Usually when you hang out with friends they can take your mind off of things but usually going shopping can help too. does it have more than one answer? if it does then D and A seem like good answers if not then D should be the answer
I would have to say the answer is C.
A is incorrect since hydrogen is not an air pollutant.
B is incorrect because ozone is most definitely one of the top.
And D has cyanide which is a chemical for suicide during wars.
Hope this helps!
