You must deploy an Azure Kubernetes Service (AKS) cluster that uses Windows Server 2019 nodes. The solution must minimize the time required to provision compute resources during scale‑out operations and must support autoscaling of Windows Server containers. Which AKS scaling option should you recommend?

The Cluster Autoscaler automatically adjusts the number of nodes in your AKS cluster based on resource requests from pods. When pods are pending due to insufficient resources, it adds new nodes, minimizing provisioning time during scale-out. It also removes nodes when they are underutilized. This directly addresses the need to minimize provisioning time and support autoscaling for Windows Server containers. Using Kubernetes version 1.20.2 or newer is a general best practice but doesn't specifically address the scaling mechanism. Virtual nodes with Virtual Kubelet and ACI allow for rapid pod provisioning on serverless ACI instances, but they don't manage the underlying AKS cluster nodes themselves, which is required for scaling Windows Server nodes. The Horizontal Pod Autoscaler scales the number of pods based on CPU/memory utilization, not the underlying nodes.