Company ABC is hiring customer service representatives from Company XYZ. The representatives reside at Company XYZ’s headquarters. Which of the following
BEST prevents Company XYZ representatives from gaining access to unauthorized Company ABC systems?

A.
Require each Company XYZ employee to use an IPSec connection to the required systems

B.
Require Company XYZ employees to establish an encrypted VDI session to the required systems

C.
Require Company ABC employees to use two-factor authentication on the required systems

D.
Require a site-to-site VPN for intercompany communications