An administrator wants to monitor virtual machines on a host and send notifications when memory usage reaches 80%.
What should the administrator create in vCenter Server to accomplish this?
A. A host alarm that will monitor virtual machine memory usage and set a trigger to email the notification.
B. A vCenter Server alarm that will monitor virtual machine memory usage and set an action to email the notification.
C. A host alarm that will monitor virtual machine memory usage and set an action to email the notification.
D. A vCenter Server alarm that will monitor virtual machine memory usage and set a trigger to email the notification.