What does STP do when a redundant path is detected?

• A. STP aggregates multiple redundant paths to increase redundancy.
• B. STP distributes IP addresses to devices.
• C. STP uses BGP to exchange topology.
• D. STP disables the redundant path to prevent loops.

Answer: (D)

Spanning Tree Protocol prevents network loops by ensuring there is only one active path between any two devices. It designates a root bridge and selects a root port on each non-root switch along with designated ports on each network segment. All other ports that could create a loop are put into a blocking state, so the redundant path is effectively disabled. If the primary path fails, STP can re-converge and move a previously blocked port into forwarding to restore the redundant path. This is not about distributing IPs, aggregating paths, or exchanging topology with BGP; the mechanism is to block the extra path to maintain a loop-free network.