Which statement about mangroves and seagrass beds is NOT correct Group of answer choices

they have ecological value

they add to water pollution by giving off sulfates

they are threatened by human activities

they provide fish nurseries

life would be meaningless without memes

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.

what school and grade?