Fleer, Inc. is a calendar-year corporation whose financial statements for 2018 and 2019 included errors as follows: Year Ending Inventory Depreciation Expense 2018 $54,000 overstated $45,000 overstated 2019 18,000 understated 15,000 understated Assume that purchases were recorded correctly and that no correcting entries were made at December 31, 2018, or at December 31, 2019. Ignoring income taxes, by how much should Fleer's retained earnings be retroactively adjusted at January 1, 2020?

Select one: a. $6,000 decrease b. $3,000 increase c. 48,000 increase d. $12,000 increase