Which of the following is NOT a type of unique individual income tax form?

A unique individual income tax form is one specifically designed for different taxpayer scenarios. The forms listed in the options serve distinct purposes and populations within the U.S. tax system.

The 1040A is a simplified version of the standard 1040 form that allows taxpayers with straightforward tax situations to file their returns more easily. It is designated for individuals whose income is above a certain threshold but below limits set for various credits and deductions.

The 1040NR is designed for non-resident aliens who need to report their U.S. income. This form is crucial for individuals who do not meet the residency requirements but have income sourced from the U.S.

The 1040PR is specifically for residents of Puerto Rico, allowing them to report their income and claim any applicable tax credits relevant to their situation on the island.

The designation R-1040, however, does not correspond to a recognized individual income tax form in the IRS system. Therefore, it is not a type of unique individual income tax form. This makes it the exception among the other forms listed, which have specific purposes and are used by particular groups of taxpayers. Understanding the nuances of these forms helps ensure compliance with tax regulations suited to individual circumstances.