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!
The answer is A
Hope I helped
Answer:
Yes.
Explanation:
Yes, creative activities are the most effective way to stretching your mental muscles because creative activities needs more focus and thinking of mind. Creative activities are done by the people to explore new things and do something new in their lives. People who are creatives are considered genius and intelligent because everybody is not able to do creative work, only small number of people can do this.
The correct answer would be D. B and C.
Hope this helps :D
