Answer:
The genetic code is degenerate.
Explanation:
The genetic code is degenerate: there are 64 triplets of different codons (sequence of three bases of mRNA that codes for a certain amino acid) and 20 amino acids. That is, an amico acid can be encoded by more than one codon.
D. An element donates an electron to another element.
I think the answer is "the older it is"
Reason: I might be wrong but is something (like a shell) gets buried in something (like sand), overtime many things (like dirt, soil, sand, etc.) will be on top of the original. This will make layers. So, the older rock is on the bottom since it has been there for the longest and it gets covered by other stuff (causing the layers).
Hope this helps! :) (If I'm wrong, sorry :( )
