Which of the following is one way to prevent the corrosion of iron?
a. add carbon to the iron. b. paint exposed iron parts with protective paint. c. let the iron develop a natural coat of carbonate. d. protect the iron from polluted air

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

let that person have a turn to speak : )