I think there was probably like 400
Organisms that use the same resources because there may not be enough for all, so it then becomes a competition of who gets it and who doesn't.
The statement which best explains why carbon is present in so many kinds of molecules is because <u>it can form four covalent bonds.
<em /></u>It isn't rare on Earth, so A is incorrect. It has valence electrons, so C is incorrect. It cannot become an ion, so D is incorrect.<u>
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The three scientist are Matthias Schleiden<span>, </span>Theodor Schwann<span>, </span>Rudolph Virchow<span> 4.
Hope it helped!</span>
The answer to your question is A carpel
