C) Joining a club, as that is a social organization.
i would say c, because many people are in need for new livers, kidneys, etc, and it does save a lot of lives per year
Ethos means attribute of spirit of a era, culture, or community. Some synonyms include: <span><span>spirit, character, atmosphere, climate, mood, feeling, tenor, or essence. Hope this helped you!</span></span>
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!
