Which of the following is a requirement for electronically filed returns?

For electronically filed returns, one of the key requirements is that they must use an IRS-authorized e-file provider. This requirement ensures the security and validity of the tax returns submitted electronically. Authorized providers are vetted by the IRS and are equipped to handle sensitive taxpayer information in compliance with established regulations and protocols. By using a provider authorized by the IRS, taxpayers can confidently submit their returns knowing that the provider has met the necessary standards for processing electronic filings.

In contrast to this correct answer, using a physical signature is not a requirement for electronic filings since the electronic transmission itself provides a form of authentication. Filing only during business hours is also not a stipulation; e-filing can be done at any time. Furthermore, filing by mail contradicts the concept of electronic filing, which is specifically designed to streamline the submission process online rather than through postal services. Thus, the requirement of using an IRS authorized e-file provider is foundational to the electronic filing system, ensuring proper handling and submission of tax returns.