Which service should a DevOps team use to deploy a multi-tier application and automate infrastructure creation?

Azure Resource Manager (ARM) templates are the correct choice because they enable Infrastructure as Code (IaC) for Azure resources. This allows a DevOps team to define the infrastructure for a multi-tier application (e.g., virtual machines, databases, networking) in a declarative JSON file. These templates can then be version-controlled and used to consistently and repeatedly deploy the entire application environment, automating infrastructure creation and ensuring consistency across deployments. Azure DevTest Labs is used for creating environments for testing and development, not for automating the deployment of production infrastructure. Azure Advisor provides recommendations for optimizing Azure resources, but it doesn't deploy or automate infrastructure. Azure Backup is for backing up and restoring data, not for infrastructure deployment.