You are a desktop support technician for your company. Your company has the following departments:

Sales: Computers belong to the corporate domain and run Windows Vista or Microsoft Windows XP Professional.
Accounting: Computers belong to the corporate domain and run Windows NT Workstation 4.0 with Service Pack 6.
Graphics: Computers belong to their own domain in a separate forest and run Windows Vista.
Research: Computers belong to a workgroup and run Windows Vista or Windows XP Professional.

You need to ensure that all the computers in the company authenticate by using Kerberos.
Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.)

A.
Upgrade all the computers in the Accounting department to Windows Vista.

B.
Join all the computers in the Research department to the corproate domain.

C.
Configure the local policy on each computer that runs Windows Vista to reject NTLM responses.

D.
Establish a forest trust between the forest that hosts the graphics department domain and the Sales department domain.