Autotrophs are the producers, i.e. plants (they make their own food) so they gain their energy by converting light energy into chemical energy through the process of photosynthesis. Whereas heterotrophs (animals) cannot make their own food so they obtain nutrition through the consumption of autotrophs and other heterotrophs.
The answer would be Flooding
<span>B. water availability determines the fauna
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I positive that the answer id D why because Without<span> them the Earth </span>would<span> be too cold for us, or any other living thing, to survive. Naturally occurring </span>greenhouse gases<span>, such as carbon dioxide and methane, allow solar radiation to reach the Earth's surface, while trapping radiation from the Earth on its way back out to space.
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