Of All the Possible Amino Acids, All Living Organisms Make

Multiple Choice

Of all the possible amino acids, all living organisms make use of only the same 20 amino acids. This supports the idea that

A) all living things are derived from a single common ancestor.
B) bacteria, animals, and plants developed independently.
C) natural selection drives evolution.
D) only a limited number of DNA mutations are possible.
E) only 20 amino acids exist on Earth.