For the following tax returns, identify the method the IRS likely used to select the return for audit from the drop$-$down box provided.

A$.$ Dan made a mistake in adding his income on his tax return.

Document perfection.

B$.$ Michael and Venita deducted a relatively large amount of travel expenses on their tax return for their business. The travel expense is large relative to other taxpayers in similar businesses with similar levels of income.

Discriminant Function $($DIF$)$ system.

C$.$ Juanita failed to report her salary from her second job on her tax return.

Information matching.