You will move a distributed on-premises application to Azure and run it across multiple VMs. To guarantee the application always runs on at least eight VMs during planned Azure maintenance, what should you create?

A Virtual Machine Scale Set (VMSS) is the correct choice because it allows you to deploy and manage a set of identical, auto-scaling virtual machines. During planned Azure maintenance, VMs in a scale set are updated in batches, ensuring that a minimum number of instances remain available. Configuring the VMSS with 10 instances guarantees that even if 20% of instances are updated at a time (a common maintenance batch size), at least eight VMs (10 - 2 = 8) will always be running. An Availability Set with three fault domains and one update domain would not guarantee eight running VMs during maintenance, as it's designed for high availability within a single datacenter, not for managing a specific number of running instances during planned maintenance across a larger set. An Availability Set with ten update domains and one fault domain is an incorrect configuration as update domains are typically limited to 20 per Availability Set, and this setup doesn't guarantee the required number of running VMs. A single virtual machine scale set configured with 12 VM instances would also work, but 10 instances is the minimum to meet the requirement, making it the most efficient correct answer.