The correct answer is C. Gains are taxed only on distribution. One of the major advantages of annuities is their tax-deferred growth . During the accumulation phase , the interest, dividends, or investment gains generated inside the annuity contract are not taxed annually . Instead, taxation is deferred until the policyholder begins taking withdrawals or receiving annuity payments. At that time, the portion of the payment representing earnings or gains becomes taxable as ordinary income. This tax deferral allows the funds inside the annuity to grow more efficiently because earnings can continue to compound without being reduced by yearly taxation.

The other options are incorrect. A is incorrect because annuity earnings are not tax deductible each year. B is also incorrect because earnings are not partially tax-exempt; rather, they are tax-deferred until distribution. D is incorrect because not all distributions are fully taxable. When annuity payments begin, part of each payment represents a return of the owner ' s principal (cost basis) and is not taxed, while only the earnings portion is subject to income tax. Therefore, the favorable tax treatment of annuities is that taxation on gains occurs only when distributions are taken