Azure NetApp Files (ANF) is a first-party, native Azure service that provides high-performance, shared file storage. It is designed for enterprise workloads like SQL databases. ANF decouples storage from compute, allowing administrators to provision and scale storage capacity and performance tiers (Service Levels) independently of the Azure Virtual Machines running the SQL Server instances. This architecture directly addresses the requirement to scale storage separately from the compute resources, making it the ideal native cloud solution for this scenario.

B. NetApp Cloud Volumes Service: This is the product name for NetApp's managed file service on Google Cloud and AWS, not on Microsoft Azure. The equivalent native service on Azure is Azure NetApp Files.

C. NetApp Cloud Volumes ONTAP: This is a customer-managed virtual storage appliance that runs on Azure VMs. Its performance is tied to the underlying VM instance type, so storage and compute are not as independently scalable as with ANF.

D. Amazon FSx for NetApp ONTAP: This is a native AWS service for deploying NetApp ONTAP file systems. The question explicitly states the company is moving to the Azure cloud, making this option incorrect.

1. NetApp Technical Report TR-4683, "Microsoft SQL Server with Azure NetApp Files":

Page 5, Section "Azure NetApp Files Overview": "Azure NetApp Files is a first-party Azure service for migrating and running the most demanding enterprise file workloads in the cloud... This architecture decouples the storage from the compute, allowing each to be scaled independently." This directly supports the independent scaling capability for SQL workloads.

2. Microsoft Azure Documentation, "What is Azure NetApp Files":

Overview Section: "Azure NetApp Files is an enterprise-class, high-performance, metered file storage service... You can create and manage Azure NetApp Files volumes using the Azure portal... It is a native Azure service." This confirms ANF's status as a native Azure solution.

3. NetApp Documentation, "Learn about Cloud Volumes ONTAP":

"What is Cloud Volumes ONTAP?" Section: "Cloud Volumes ONTAP is a software-only storage appliance that runs the NetApp ONTAP data management software in an AWS, Azure, or Google Cloud environment." This clarifies that CVO is a software appliance running on cloud compute, not a native, fully managed storage service like ANF.