The workstation used by the marketing director in your company has been successfully hacked through the open Telnet port, even though she does not use Telnet. What step should be taken to thwart...

The workstation used by the marketing director in your company has been successfully hacked through the open Telnet port, even though she does not use Telnet. What step should be taken to thwart future attacks?

a. Close all TCP ports.

b. Reduce the Telnet port’s bandwidth.

c. Close TCP and UDP port 23.

d. Configure Telnet so that it cannot be used in the background mode.