What is the role of a device that is simultaneously functioning as both the distribution...

In a hierarchical network model, the role of a device functioning simultaneously as both the distribution and core is most accurately described as "FortiGate managing FortiSwitch (B)." In this setup, FortiGate acts as the central unit managing multiple FortiSwitch units, thereby functioning both as a distribution layer—handling traffic between network segments—and as a core layer—managing traffic within the network on a broader scale. This setup is typical in medium-sized networks where a single device is capable enough to handle both roles effectively.