Aquatic environments, mainly the sea.
X: Ozone layer destruction
Y: Mass extinction
Answer:
Answer in order: C, A, B
Explanation:
But I'm not the brightest at this subject, but what I did is just observed what I thought the answers were thoroughly by using the keywords and letters and then matching them together to make sense. I remember doing this, but let me know if it's wrong!
A molecule is made of more than one atom of differing elements that can be simplified while an element cannot be simplified because it is only one atom of one type of element.
