The information related to the virtual infrastructure that is missing and must be collected during the discovery are the total number of virtual machines and the size of the source data set. These are essential metrics for sizing the backup components, such as proxies, repositories, and transporters, as well as estimating the backup storage requirements and bandwidth consumption. The other options are either already provided in the scenario (recovery time objective, backup window) or not relevant for the Veeam solution (speed of Fibre Channel fabric). References: Veeam Certified Architect 2022 Exam Guide, page 10; Veeam Backup & Replication v11: Architecture and Design course, module 3.