The process of fermentation takes place

Fermentation is an anaerobic process in which energy can be released from glucose even though oxygen is not available.

Explanation:

Fermentation occurs in yeast cells, and a form of fermentation takes place in bacteria and in the muscle cells of animals.

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.

i think its the first one