False teeth help the digestive system by chewing pieces of food into smaller pieces but it is not part of it.
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True. It also states that they cannot compete for the same resources.<span />
The best and most correct answer among the choices provided by the question is <span>b. oil</span> <span>.
</span>A thick, black liquid formed from the buried remains of microscopic marine organisms is oil .
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Hope my answer would be a great help for you. </span>
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It may become endangered </h2>
Explanation: <u><em>If organisms cannot adapt to the changes in their ecosystem, they may move to another location. If they will not move, the species may become threatened, endangered, or extinct. Under an evolutionary phenomenon called relaxed selection, traits that were advantageous in one time and place become obsolete in another. Traits that aren't actively maintained by natural selection tend to become smaller or less functional over time, studies suggest.</em></u>