A passive network hub operates at which layer of the OSI model?

A passive network hub operates at the Physical Layer of the OSI model. This layer is responsible for the transmission and reception of raw bitstreams over a physical medium. Passive hubs function primarily as a connection point for devices on a network, allowing them to communicate by broadcasting data packets to all connected devices without any filtering or processing involved.

Since they do not handle data packets at the Data Link Layer, such as addressing or error-checking, their operations are limited to simply facilitating the physical connections. This makes them a straightforward component of network architecture focused solely on the physical connection and transmission, which is why the correct answer is the Physical Layer.