Referring to the figure below, please identify the letter of the choice that best matches the numbered area on the screen.

Which of the following would be used on a network to ensure access to resources if a critical host becomes unavailable?

A. QoS B. CARP C. VLAN D. DHCP server

When representing a stack as a linked list, all _________ and __________ are done at the list head.

Fill in the blank(s) with the appropriate word(s).