A company is testing an application running on an Amazon EC2 Linux instance. A single 500 GB Amazon Elastic Block Store (Amazon EBS) General Purpose SSD (gp2) volume is attached to the EC2 instance. The company will deploy the application on multiple EC2 instances in an Auto Scaling group. All instances require access to the data stored on the EBS volume. The company needs a highly available and resilient solution that does not require significant application code changes. Which solution meets these requirements?

Amazon EFS is the correct solution because it provides a highly available, resilient, and scalable network file system that can be mounted by multiple EC2 instances concurrently. This directly addresses the requirement for all instances in an Auto Scaling group to access the same data without significant application changes. General Purpose performance mode is suitable for most workloads. Provisioning an EC2 instance as an NFS server creates a single point of failure and requires manual management, which is not highly available or resilient. Amazon FSx for Windows File Server is designed for Windows-based workloads and SMB, not Linux EC2 instances, and configuring it in a single Availability Zone limits resilience. Provisioning two EBS volumes on a single EC2 instance does not allow multiple instances to share data, nor does it inherently provide high availability or resilience for shared access.