I believe it’s Precambrian.
Answer:
<u>prokaryotes</u>
Explanation:
The first living things on Earth, single-celled micro-organisms or microbes lacking a cell nucleus or cell membrane known as <u><em>prokaryotes</em></u>, seem to have first appeared on Earth almost four billion years ago, just a few hundred million years after the formation of the Earth itself.
<em>HOPE THIS HELPED </em>
<em>MARK BRAINLIEST</em>
The answer you are looking is the carbon cycle.
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