A foreign auto manufacturer has spent $\backslash (\backslash$$ $200\backslash )$ million constructing a new plant in Lincoln, Nebraska. It will cost the firm another $\backslash (\backslash$$ $2\backslash )$ billion to finish the project, but questions have come up over whether building the plant in Lincoln is wise after all. When deciding whether to continue the project, the firm's chief financial officer tells the board of directors to ignore the $\backslash (\backslash$$ $200\backslash )$ million because it

doesn't factor into the total cost of the project.

can be recovered if the project is stopped.

is a sunk cost.

is less than one$-$tenth of the entire project cost.

is a variable cost.