Which supplemental schedule may be required for Riana if her total taxable interest exceeds a certain limit?

When an individual's total taxable interest exceeds $1,500, they are required to complete Schedule B. This schedule is specifically designed to report interest and ordinary dividends. It provides a detailed breakdown of the sources of interest income and helps ensure that all income is accurately reported on the tax return.

Schedule A is primarily used for itemized deductions, Schedule C is for profit or loss from a business, and Schedule D is focused on capital gains and losses. Therefore, these schedules are not applicable in the context of reporting excess interest income. Schedule B's purpose directly aligns with the reporting needs when taxable interest exceeds the specified limit.