Estuaries are a large group of small fish that use coral reefs to protect them
It is a vestigial Structure.
Explanation:
I believe the correct answer is the final option - <span>If Earth formations can change over time, it is possible that even life on earth could change over millions of years.
Given that Darwin proposed his ideas about the origins of species and evolution, this is the only possible option to choose. It is impossible that life doesn't change at all, and millions of years are a long time to implement those changes. So it is only natural that organisms can change as much as the Earth can.
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