A Security Administrator Needs an External Vendor to Correct an Urgent

A security administrator needs an external vendor to correct an urgent issue with an organization's physical access control system (PACS) . The PACS does not currently have internet access because it is running a legacy operation system. Which of the following methods should the security administrator select the best balances security and efficiency?

A) Temporarily permit outbound internet access for the pacs so desktop sharing can be set up
B) Have the external vendor come onsite and provide access to the PACS directly
C) Set up VPN concentrator for the vendor and restrict access to the PACS using desktop sharing
D) Set up a web conference on the administrator's pc; then remotely connect to the pacs