Which statement about BPDU is true?

• A. BPDU is used to secure SNMP communications.
• B. BPDU is used to identify device models.
• C. BPDU is used to measure traffic latency.
• D. BPDU determines the topology of the network.

Answer: (D)

BPDU stands for Bridge Protocol Data Unit, a message used by the Spanning Tree Protocol to learn and share information about the network’s switching devices so a loop-free topology can be built. By exchanging BPDUs, switches elect a root bridge and advertise path costs, allowing each switch to determine which ports should forward and which should block. This process creates and maintains the network’s topology, adapting as links change to prevent loops. The other statements don’t fit because securing SNMP communications is handled by SNMP itself (not BPDUs), identifying device models is done by discovery protocols like LLDP or CDP, and measuring traffic latency is outside the purpose of BPDUs.