Which account reflects adjustments to the fair value of equity portfolios at year-end?

The Fair Value Adjustment (FVA) account is the correct choice because it specifically captures the adjustments made to reflect the fair value of equity portfolios at year-end. Under fair value accounting, changes in the value of these portfolios must be reported to give an accurate picture of their current worth, which is critical for financial reporting.

The FVA account recognizes unrealized gains and losses on investments without requiring the sale of the underlying assets. This adjustment is essential for presenting a true and fair view of a company's financial position, as it updates the carrying value of these portfolios on the balance sheet to reflect their market value at the reporting date.

In contrast, other accounts mentioned do not serve this specific purpose. The Unrealized Holding Gain or Loss - Income account reflects similar gains or losses but is focused on the impact on income rather than the fair value adjustment process itself. The Cash Account and the Dividend Revenue Account relate to transactions involving cash flows rather than the valuation of equity portfolios, thus making them irrelevant to the question about year-end fair value adjustments.