For the answer to the question above, I believe the answer is <span>"The forelimbs are similar because all of these organisms inherited the basic forelimb design from a common ancestor."
We've just evolved from our ancestor.
I hope my answer helped
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The answer to the question is d
Answer:
It's electron structure.
Explanation: The valence levels and the amount of electrons allows for the covalent bonding with multiple other elements.