When is the page file for a Windows guest OS or the swap partition for a Linux guest OS created?

A.
When the Virtual Machine is created

B.
When a Virtual Machine is first powered on

C.
When the Guest OS is installed on the Virtual Machine

D.
When a reservation is set for the Virtual Machine

Explanation:
Understanding the files that make up a VMware virtual machine

When you power on a VM, a memory swap file is created that can be used in lieu of physical host memory if an ESX host exhausts all of its physical memory because it is overcommitted. These files are deleted when a VM is powered off or suspended.