please answer and explain

Carpark Services began operations in 20X1 and maintains long-term investments in available-for-sale securities. The year-end cost and fair values for its portfolio of these investments follow. The year-end adjusting entry to record the unrealized gain/loss at December 31, 20X1 is: Available-for-Sale Securities December 31, 20X1 December 31, 20X2 December 31, 20X3 O Debit Fair Value Adjustment - Available-for-Sale (LT) $9500; Credit Unrealized Gain - Equity $9500 O Debit Unrealized Loss - Income $9500; Credit Fair Value Adjustment - Available-for-Sale (ST) $9500 O Debit Unrealized Loss - Equity $9500; Credit Fair Value Adjustment - Available-for-Sale (LT) $9500. O Debit Fair Value Adjustment - Available-for-Sale (LT) $9500; Credit Unrealized Loss - Equity $9500. O Debit Unrealized Gain- Equity $9500; Credit Fair Value Adjustment - Available-for-Sale (LT) $9500 Cost Fair Value 350,00 420,00 490,00 340,50 431,50 550,00