What cell structure consists of a network
of protein filaments and tubules that
allows cells to keep their shape?

as resources become scarce because of population growth, the growth decreases after few years due to lack of resources and food.

climate change and pollution

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

idk lol use google m8