The answer is C because, Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species.
I think it's the first and second option but I could be wrong because I don't know much about deserts :)
The exoskeleton of an arthropod is chitin.
The answer would be thermal insulator, hope it works goodluck
Hello!
The best representation is "C. A cactus is moved from a sunny windowsill to a dark room..", because the cactus feed itself with photosyntesis.
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