Which of the following is not a title for a Drill Sergeant listed in the set?

The reason SDS Burnett is the correct answer is that the title "SDS" stands for "Staff Drill Sergeant," which is not a standard title typically used to refer to Drill Sergeants in the Army. The common titles associated with Drill Sergeants are designated as "DS," which stands for "Drill Sergeant." The other choices all include this appropriate designation, confirming their status within the role. In the context of the Army's structure and terminology, using DS indicates the rank and responsibilities of the individuals conducting training, while SDS is less commonly used and might imply a higher or different role within the Drill Sergeant hierarchy, making it the exception in this list.