Consider the Workstation relation shown in the exhibit. This relation tracks PC workstations within a company facility. The MAC address is a number burned into the replaceable network card in each computer. The IP address indicates the computer's current location on the company network. The asset number is a number on an inventory control tag affixed to the back of each computer. The Location indicates the particular room inside the facility in which the computer is located. The User field indicates the current user. Which attribute is the most appropriate for use as the primary key?
