15. Which of the following is correct regarding self-employment taxes? I. For purposes of the portion of self-employment tax that is equivalent to Social Security tax, taxable self-employment income is limited to a prescribed maximum amount reduced by other wages earned by the taxpayer that are subject to FICA and Medicare taxes. II. For purposes of the portion of self-employment tax that is equivalent to the Medicare tax, taxable self-employment income is limited to a prescribed maximum amount reduced by other wages earned by the taxpayer that are subject to FICA and Medicare taxes. I only II only Neither I or II I and II