Starling Co. is considering disposing of a machine with a book value of $24,500 and estimated remaining life of five years. The old machine can be sold for $6,000. A new high-speed machine can be purchased at a cost of 69,700. It will have a useful life of five years and no residual value. It is estimated that the annual variable manufacturing costs will be reduced from $23,000 to $19,600 if the new machine is purchased. The differential effect on income for the new machine for the entire five years is

A) increase of $60,710

B) increase of $46,700

C) decrease of $46,700

D) decrease of $60,710