The correct answer is Spanning Tree because broadcast storms are typically caused by Layer 2 switching loops in Ethernet networks. According to the CompTIA Network+ (N10-009) objectives under switching concepts, the Spanning Tree Protocol (STP) is specifically designed to prevent loops in networks that have redundant switch connections.
In a Layer 2 environment, switches forward broadcast frames out all ports except the one on which they were received. If redundant paths exist without STP, frames can circulate indefinitely, creating a broadcast storm. This results in excessive traffic, high CPU utilization on switches, MAC address table instability, and significant network performance degradation.
STP prevents this by logically blocking redundant paths while maintaining them as backups. If the active path fails, STP recalculates and activates a previously blocked path, preserving redundancy without loops.
The other options—EIGRP and BGP (routing protocols) and CDP and LLDP (device discovery protocols)—do not prevent Layer 2 loops.
Therefore, configuring Spanning Tree Protocol is the appropriate solution to mitigate broadcast storms.