Which service should you use to configure the virtual machines that have the Pool1 prefix?

Azure Automation is the correct choice because it provides a cloud-based automation service that allows you to create, schedule, and manage runbooks to automate tasks across Azure and non-Azure environments. For configuring virtual machines with a specific prefix like "Pool1," you can write PowerShell or Python runbooks within Azure Automation to apply configurations, install software, or perform other management tasks on those VMs. An Azure Virtual Desktop automation task is a more general term and not a specific Azure service. Virtual machine auto-shutdown is a feature for cost management, not configuration. Service Health in Azure Monitor provides information about the health of Azure services, not a tool for VM configuration.