A rack diagram is the most suitable choice because it provides a detailed visual representation of the physical organization of the equipment in the racks, which is ideal for troubleshooting physical connectivity issues, planning upgrades, and guiding future changes. While a floor plan can show locations of network devices within a building, it does not offer the level of detail regarding the organization within the racks. A logical network diagram provides an abstracted view of the network, focusing on how the devices interact at a higher level, not their physical arrangement. A wiring diagram, although useful, typically details the cabling rather than equipment organization.