On December 31 the fair value of available-for-sale securities is $41,300 and the cost is $39,800, On January 1, 2020, there was a credit balance of $900 in the Fair Value Adjustment --Available-for-Sale account. The required adjusting entry would be O debit Fair Value Adjustment-Available-for-Sale for $2,400 and credit Unrealized Gain or Loss-Equity for $2,400. O debit Fair Value Adjustment-Available-for-Sale for $1,500 and credit Unrealized Gain or Loss-Equity for $1,500. O debit Unrealized Gain or Loss --Equity for $2,400 and credit Fair Value Adjustment -- Available-for-Sale for $2,400. O debit Fair Value Adjustment-Available for Sale for $600 and credit Unrealized Gain or Loss --Equity for $600