At December 31, 2020, the available-for-sale debt portfolio for Vaughn, Inc. is as follows. Security Cost Fair Value Unrealized Gain (Loss) A $21,000 $18,000 $(3,000) B 15,000 16,800 1,800 C 27,600 30,600 3,000 Total $63,600 $65,400 1,800 Previous fair value adjustment balance-Dr. 480 Fair value adjustment-Dr. $1,320 On January 20, 2021, Vaughn, Inc. sold security A for $18,120. The sale proceeds are net of brokerage fees. (a) Your answer is partially correct. Prepare the adjusting entry at December 31, 2020, to report the portfolio at fair value. (Credit account titles are automatically indented when amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter O for the amounts.) Account Titles and Explanation Cash Debt Investments Debit Credit 18,120 18.120