Azure NetApp Files volumes need to be placed in a specially purposed subnet within your Azure Virtual Network (VNet) to ensure proper isolation and security. This subnet must bedelegatedspecifically to Azure NetApp Files services.
Adelegated subnetin Azure allows certain Azure resources (like Azure NetApp Files) to have exclusive use of that subnet. It ensures that no other services or VMs can be deployed in that subnet, enhancing security and performance. Moreover, it ensures that the volumes are only accessible through private connectivity options like VNet peering or a Virtual Network Gateway, without any exposure to the public internet.
Subnets such asbasic,default, ordedicateddo not have the specific delegation capabilities required for Azure NetApp Files, makingdelegatedthe correct answer for this scenario.