What Azure feature enforces that only approved virtual machine types are used in an environment?

Azure Policy is the correct answer because it allows you to define and enforce standards for your Azure resources. You can create policies that audit or deny the deployment of specific virtual machine (VM) sizes or types, ensuring compliance with organizational requirements. Azure Resource Locks prevent accidental deletion or modification of resources, but don't restrict resource creation based on type. Azure Cost Management helps track and optimize spending, but doesn't enforce resource types. Azure Activity Log records events that occurred in your Azure subscription, but doesn't prevent non-compliant deployments.