Which of the following is not a system role in vCenter?

Which of the following is not a system role in vCenter?

• Administrator
• Read Only
• No Access
• Virtual Machine User (Power User) 

EXPLANATION

Virtual Machine User is a sample role on the vCenter system of permissions - No Access, Administrator and Read Only are the system roles which are not customizable.

SOURCE

https://pubs.vmware.com/vsphere-60/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-60-security-guide.pdf