What function on VMware allows the manual or automatic distribution of VM's between hosts for a balanced computing resourse?

What function on VMware allows the manual or automatic distribution of VM's between hosts for a balanced computing resourse?

• X-Switch vMotion
• DRS
• HA
• vMotion 

EXPLANATION

VMware DRS (Distributed Resource Scheduler) is a utility that balances computing workloads with available resources in a virtualized environment. The utility is part of a virtualization suite called VMware Infrastructure 3.
With VMware DRS, users define the rules for allocation of physical resources among virtual machines. The utility can be configured for manual or automatic control. Resource pools can be easily added, removed or reorganized. If desired, resource pools can be isolated between different business units. If the workload on one or more virtual machines drastically changes, VMware DRS redistributes the virtual machines among the physical servers. If the overall workload decreases, some of the physical servers can be temporarily powered-down and the workload consolidated.

SOURCE

https://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.wssdk.pg.doc_50%2FPG_Ch13_Resources.15.6.html