Which service is suitable for infrequently used data storage?

Amazon Glacier is specifically designed for infrequently accessed data storage, making it a cost-effective solution for archiving data that does not require immediate access. It provides very low storage costs compared to other storage options, which is ideal for long-term data archiving, backups, and compliance.

Users can store large amounts of data in Glacier and retrieve it when necessary, although retrieval times can vary from minutes to hours depending on the retrieval option selected. This tiered retrieval architecture is built specifically for users who can afford some latency for accessing their data.

In contrast, the other services serve different purposes. Amazon EFS is designed for applications that require file storage with low-latency access and supports concurrent access from multiple instances, making it less suitable for infrequently accessed data. Amazon S3 is a versatile storage service that can accommodate both frequently and infrequently accessed data, but it not specifically optimized for long-term archiving. Amazon EBS is meant for block storage and is typically attached to EC2 instances for immediate data access and performance, not for infrequent access needs.