Which of the following statements about traditional IRAs is TRUE?

A. Taxable investment income, such as interest, dividends, and capital gains, will qualify as compensation for the purpose of contributing to an IRA.

B. Taxpayers may be able to reduce their tax liability by contributing to an IRA after the tax year has ended.

C. Taxpayers with a timely filed extension have until October 15 of the tax year to establish and contribute to an IRA.

D. Taxpayers who participate in an employer-sponsored retirement plan are prohibited from contributing to an IRA.