Which document is used to issue material to a Local Element?

The SF-153, also known as the "COMSEC Material Report," is the correct document used to issue material to a Local Element. This form plays a crucial role in the communication security (COMSEC) management process by ensuring that sensitive material is properly accounted for and documented when it is distributed.

When a Local Element requires COMSEC material, the SF-153 serves as an official record that details what is being issued, to whom, and for what purpose, thereby maintaining a chain of custody and accountability for classified information. This is essential in safeguarding national security by preventing unauthorized access to sensitive materials.

The other options do not fulfill the same role within the context of COMSEC. For instance, the SF-86 is a form used for background checks for security clearances, the DD-250 is related to the delivery of supplies and services in contracting, and the AF Form 321 is typically used for administering training and unit manning. None of these documents specifically target the issuance and accountability of COMSEC material like the SF-153 does.