Which of the following is NOT a type of taxable income?

Social security benefits based on disability may not always be included in taxable income, depending on the taxpayer's overall income. Specifically, if a taxpayer’s provisional income, which includes adjusted gross income, tax-exempt interest, and half of the social security benefits, is below a certain threshold, then a portion or all of those benefits could be non-taxable.

In contrast, rental income, interest income, and capital gains are generally considered taxable income and must be reported on tax returns. Rental income is earnings derived from leasing property, interest income is the money earned from lending or saving, and capital gains arise from the sale of assets at a profit. Each of these income types is universally recognized as taxable under the Internal Revenue Code.