If a person consumed large quantities of deep yellow/orange or dark green foods that are dietary sources of carotenoids, the foods produce harmful effects in the body because the rate of conversion to the animal form, retinal, is

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.

some inherited genetic mutations can be good for the offspring, so the answer is different genetic mutations cause many forms of cancer.