What is a possible cause of this problem?

A VirtualCenter Administrator assigned you Administrator privileges on an ESX Server
Cluster. You are unable to connect the Virtual Infrastructure Client to the ESX Server
directly. What is a possible cause of this problem?

A.
You need Administrator privileges on the server and all of its resource pools.

B.
You still have a Virtual Infrastructure Client connected to the VirtualCenter server.

C.
Administrators are not allowed to log in to ESX Servers.

D.
User names and permissions are not propagated from VirtualCenter to ESX Servers.

Explanation:
Basic System Administration ESX Server 3.5, ESX Server 3i version 3.5 VirtualCenter
2.5, page 265, 266.
A user is an individual authorized to log in to an ESX Server host or to VirtualCenter.
Users on a host fall into two categories: those who can access the ESX Server host
through VirtualCenter and those who can access the host by directly logging in to the
host from VI Client, VI Web Access, a third?party client, or a command shell. These two
categories draw users from different sources:
VirtualCenter users – Authorized users for VirtualCenter are those included in the
Windows domain list referenced by VirtualCenter or local Windows users on the
VirtualCenter host.
Direct access users – Users authorized to work directly on an ESX Server host are those
added to the internal user list by default when ESX Server is installed or by a system
administrator after installation.
Even if the lists maintained by an ESX Server host and VirtualCenter appear to have
common users (for instance, a user called devuser), these users should be treated as
separate users who have the same name