What is a primary function of spanning tree protocol in a network?

The primary function of the Spanning Tree Protocol (STP) is to prevent loops in a network topology. In Ethernet networks, where switches connect multiple devices, the potential for broadcast storms and data packet loops exists. When there are multiple paths between switches, frames can get stuck in a loop, continuously circulating and causing network congestion or failure.

STP addresses this issue by creating a loop-free logical topology. It accomplishes this by selectively blocking some of the redundant paths while allowing only one active path between any two network devices. The protocol dynamically identifies and disables those paths to maintain a single active route and allows for the creation of backup paths that can be enabled if the primary path fails. This ensures efficient data transmission without the risk of loops that can disrupt the entire network.

While other options touch on various aspects of networking, they do not accurately describe the core function of STP. For instance, improving data transmission speed, securing transmissions, or facilitating switch management are not direct purposes of STP. Instead, STP is fundamentally about maintaining an organized and efficient network structure by eliminating the possibility of loops, making option B the correct choice.