A network administrator notices that when a particular legacy device is connected to a switch port, the network experiences slowdowns. The device is necessary for certain operations but is known to operate in half$-$duplex mode.

What is the most likely cause of the network slowdowns, and how can the administrator mitigate this issue?

The legacy device is causing collisions on the switch port; the administrator should configure the port to operate in full$-$duplex mode.

The switch port is incorrectly configured to prioritize traffic, leading to network congestion; the administrator should adjust the Quality of Service $($QoS$)$ settings.

The entire switch is slowing down due to the high$-$speed requirements of the legacy device; the administrator should upgrade the switch to a higher capacity model. $q,$ The switch is automatically configuring VLANs, causing compatibility issues; the administrator should disable VLANs on the port connected to the legacy device.