What qualification requirement is common across the 5-level, 7-level, and 9-level positions?

The correct answer emphasizes the importance of having both a supervisor's recommendation and the commander's approval as part of the qualification process for various levels within the administration career field. This requirement ensures that individuals moving up in rank or responsibility are not only competent in their skills but also meet the standards set by their immediate supervisors and commanders. Supervisor recommendations indicate that the individual has demonstrated the necessary performance and reliability in their current role, while the commander's approval serves as a final confirmation of the individual’s readiness to advance. This dual approval system helps maintain high standards within the organization and ensures that personnel are fully qualified for the responsibilities they are about to undertake across the 5-level, 7-level, and 9-level positions.

Other options like completion of advanced training, passing a written exam, or having specific on-the-job training hours are important in their own contexts but do not serve as a universal requirement across all levels mentioned. Each of those may apply in certain situations but they are not consistent across the different levels of positions within the administration structure.