I think it’s
C, decreased sources diversity
Well, I know logically that both life and environment change over time. So I think the answer would be C, studying fossils shows us that both life and environments change over time. Hope this helps.
Helium, with two protons, will have two electrons. In the chemical classroom, the proton count will always be equivalent to an atom's atomic number. This value will not change unless the nucleus decays or is bombarded (nuclear physics). Figure \(\PageIndex{1}\): The periodic table of the elements.