Final Answer:
If there are 2 ports with equal-cost paths to the root in a Spanning Tree Protocol (STP) network, the designated port is selected based on A. Lowest MAC address.
Step-by-step explanation:
In a Spanning Tree Protocol (STP) network, the designated port is the port on a switch that provides the most direct path to the root bridge. When there are multiple ports with equal cost (equal path cost) to the root bridge, the tie-breaker for selecting the designated port is the lowest MAC address.
The STP algorithm uses the Bridge Protocol Data Units (BPDUs) to determine the network topology and select the designated ports to prevent loops in the network.
The MAC address tie-breaker ensures a deterministic method for choosing the designated port when there are multiple paths with the same cost.
In summary, in the scenario of equal-cost paths to the root in an STP network, the designated port is selected based on the lowest MAC address.