The correct choice is Amazon WorkSpaces. This service is offered by AWS as a managed Desktop as a Service solution that is delivered globally and it enables organizations to provision and manage virtual desktops for users around the world.

Amazon WorkSpaces is designed as a globally delivered desktop service with centralized management and user access across many locations. That global delivery model is what makes it the proper selection when the requirement calls for a service provided at a global scope by default.

Amazon Elastic File System (Amazon EFS) is regional because each file system exists within a specific AWS Region and operations target that regional resource.

AWS Snowball is a physical data transfer appliance and associated service that is used per job and per participating Region rather than being provided as a global service by default.

Amazon Simple Storage Service (Amazon S3) buckets are created in a particular Region and data residency is tied to that Region even though some S3 features operate globally. This regional characteristic makes S3 buckets an incorrect choice for a service required to be global by default.

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