A.Snapshots

B.Bus Sharing

C.vSphere HA

D.Storage I/O Control

A.It records user actions or system actions that occur on objects in
vCenter Server or on a host.

B.It notifies about events or conditions that occur with an object on
vCenter Server.

C.It represents system activities that do not complete immediately, such
as migrating a virtual machine.

D.It keeps records of system actions and the frequency at which they
occur.