Which of the following statements about the depletion deduction is false? A. Firms can deduct the greater of cost depletion or percentage depletion for the year. B. Percentage depletion is a tax preference item. C. The depletion deduction can never exceed the unrecovered cost basis in the depletable asset. D. Percentage depletion is not based on any actual decrease in the expected productive value of a mine or well.