Southport Company is considering the purchase of a piece of equipment that costs $100,000. The equipment would be depreciated on a straight-line basis to its expected salvage value of $10,000 over its 16-year useful life. Assuming a tax rate of 40%, what is the annual amount of the depreciation tax shield provided by this investment?
A. $4,000
B. $9,000
C. $3,600
D. None of these.