Photosynthesis is primarily carried out by autotrophs , which include plants and algae. Other options like nektons, heterotrophs, and zooplanktons do not perform photosynthesis. Thus, the correct answer is autotrophs. ;
Photosynthesis is performed by autotrophs, which include plants and some bacteria. Nektons, heterotrophs, and zooplanktons do not conduct photosynthesis. Therefore, the correct answer is autotrophs.
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