Explanation

Amazon FSx is the correct answer because it provides fully managed Windows file servers specifically designed for Windows-based applications.

Why Amazon FSx is correct:

• Fully managed Windows file server: Amazon FSx for Windows File Server provides fully managed, native Windows file systems
• Windows compatibility: Built on Windows Server, providing full compatibility with Windows applications
• SMB protocol support: Supports the Server Message Block (SMB) protocol used by Windows applications
• Active Directory integration: Integrates with AWS Directory Service or your on-premises Active Directory
• Native features: Supports Windows file system features like NTFS permissions, shadow copies, and VSS

Why other options are incorrect:

• Amazon EKS (B): Managed Kubernetes service for container orchestration, not file storage
• Amazon ECS (C): Container orchestration service for Docker containers, not file servers
• Amazon EMR (D): Big data platform for processing large datasets using frameworks like Hadoop and Spark

Amazon FSx is specifically designed to provide fully managed Windows file shares that are accessible from Windows-based applications running on AWS or on-premises.