Recommend an Azure Storage configuration that meets these requirements: stores 1 PB of blob data, supports three levels of subfolders, and supports access control lists (ACLs). Which configuration should you use?

The correct answer is a general-purpose v2 storage account with Hierarchical Namespace enabled. This configuration is essential because it supports Azure Data Lake Storage Gen2, which provides a hierarchical namespace. A hierarchical namespace is crucial for organizing data into directories and subdirectories (like the required three levels of subfolders) and for enabling POSIX-compliant access control lists (ACLs). General-purpose v2 accounts are also suitable for large-scale blob storage, easily accommodating 1 PB of data. Premium storage accounts for block blobs or page blobs do not inherently offer a hierarchical namespace or ACLs in the same way Data Lake Storage Gen2 does. While premium block blobs offer high performance, they lack the directory structure and ACL features. Premium storage accounts configured for file shares are designed for SMB/NFS file access, not for blob storage with hierarchical namespaces and ACLs as described.