What form is used for formal complaints?

The correct response identifies DA Form 7279-R as the appropriate form for submitting formal complaints. This form is specifically designed to facilitate the reporting and handling of complaints within military and defense contexts, ensuring that grievances can be addressed through the proper channels. By utilizing this form, individuals can ensure that their complaints are officially documented and processed following established procedures.

The other forms listed do not serve the same purpose as DA Form 7279-R. Each form typically addresses different administrative needs or functions within military operations, which is why they would not be suitable for filing formal complaints. Thus, when a formal complaint needs to be made, DA Form 7279-R is the correct choice, as it aligns with the structured process required for lodging complaints in a formal manner within the military framework.