Which AWS service or device should the company use to meet this requirement?

Explanations:

AWS Backup is a service designed for backing up data and restoring it, but it does not provide a file system interface for shared access among multiple EC2 instances. It is primarily focused on data protection rather than file sharing.

Amazon Elastic File System (Amazon EFS) is a fully managed, scalable file storage service that can be accessed by multiple EC2 instances simultaneously. It supports shared file storage across different Availability Zones, making it ideal for applications needing access to a common set of files.

Amazon Elastic Block Store (Amazon EBS) provides block storage volumes for use with EC2 instances, but it is designed for single-instance attachment. EBS volumes cannot be shared directly across multiple instances, which makes them unsuitable for applications that require concurrent access to the same files.

AWS Snowball Edge Storage Optimized is a data transfer device that helps in migrating large amounts of data to and from AWS. While it provides local storage capabilities, it is not suitable for providing a common file system for EC2 instances. It is primarily used for data transfer rather than as a file sharing solution.