Which vSphere DRS Automation Level should an administrator use to ensure initial placement of virtual machines is automatically performed and migration recommendations are displayed but not applied?

The correct choice is Partially Automated because this vSphere DRS (Distributed Resource Scheduler) automation level allows for the initial placement of virtual machines to be handled automatically by the system. In this mode, DRS makes recommendations for virtual machine migrations based on resource utilization and other optimization criteria, but these recommendations require administrator approval before being applied. This is an important feature for environments where an administrator wants to oversee changes, ensuring that any recommended migrations can be reviewed for their impact before being enacted.

In contrast, the Manual setting would not automatically manage the placement of virtual machines at all, requiring the administrator to handle everything manually, which does not meet the requirement of automatic initial placement. The Fully Automated mode would apply all recommendations without any review, which also doesn't align with the need for oversight in migrations. Aggressive mode goes beyond merely recommending and applying migrations more frequently, yet it doesn't offer the balancing approach of oversight that the Partially Automated level provides. Thus, Partially Automated strikes the right balance between automation and administrative control.