Answer:
A. homologous structures
Explanation:
The answer is homologous structures.
A male cat and a male dog both have masculine penile <em>structures. </em>
They are are two different organisms, but the two penises are in a similar form because they are both penises.
Same Structures = Homo Structures
Same with any other parts
Respiration is the ability to break down nutrients to make energy, so the answer should be the fourth option.
That would be Chemoautotrophic
As the earth has active tectonics we know that rocks are recycled and the oldest rocks may therefore just be the oldest rocks that have not been recycled yet. We know the true age of the earth by looking at radioactive isotopes of things like spacedust and meteors that formed at the same time as the earth as they have not been affected by the tectonic process of recycling here on Earth.