The best answer isAPI Gateway + SQS + DLQ + Lambdabecause it combines API ingestion with durable queuing and asynchronous processing. AWS guidance for event-driven serverless architectures specifically recommends usingAmazon SQSto decouple components and durably persist messages when downstream processing is slower or bursty. AWS also documents thatdead-letter queueshelp isolate messages that fail processing, which supports the requirement to avoid losing requests. API Gateway can integrate with AWS services, including SQS, to accept requests from mobile and web clients. The ALB options do not provide the same durable buffering, and the SNS option is less appropriate because the key requirement is loose coupling with durable request preservation. Therefore,Bis the strongest design. (AWS Documentation)

Automated backupsare the correct answer because Amazon RDS uses daily automated backups together with transaction logs to support point-in-time recovery. AWS documentation states that RDS can retain automated backups for up to 35 days and uploads transaction logs every 5 minutes, which supports restoring to a specific point in time with a maximum of about 5 minutes of data loss. Read replicas are mainly for scaling reads, not for fine-grained restore after accidental edits. Manual snapshots are point-in-time copies, but they do not provide continuous point-in-time recovery. Multi-AZ improves availability, not historical recovery from user mistakes. Therefore, automated backups are the right feature for this data-loss recovery requirement. (AWS Documentation)

AWS documentation states that for API Gateway REST APIs, AWS WAF must be deployed in the same Region to apply web access control lists. WAF geographic match rules can block requests from non-US Regions. Deploying the WAF and API Gateway in the same Region ensures minimal latency because the traffic does not traverse Regions.
Options B and C violate the requirement that WAF and API Gateway must be in the same Region. Option D uses HTTP API, which supports WAF only indirectly via regional ALBs, not directly as REST API does.

Amazon EFS provides a shared, fully managed, POSIX-compliant file system that can be mounted by all EC2 instances. Any update made to the file system is immediately visible to all instances, ensuring every new instance has the latest product manuals without delay.
EFS automatically scales storage and throughput, meeting high-demand conditions with no application changes required.
S3 requires instances to download files locally, causing delay and stale data issues (Options B and D).
Instance store volumes (Option A) are ephemeral and not shared, making them unsuitable for consistent data distribution.

S3 File Gateway is the right gateway type because the on-premises workload needsNFS-based file accesswhile storing data in Amazon S3. AWS documentation states that File Gateway exposes NFS and SMB shares backed by S3 objects. For the archive requirement, the company is willing to wait days for retrieval, which aligns withS3 Glacier Deep Archive, AWS's lowest-cost archival storage class for long-term retention.
A lifecycle policy can transition the data automatically after 5 days. Volume Gateway is block-oriented, not NFS file-based, and Tape Gateway is intended for backup applications that use virtual tapes rather than standard NFS file shares. Therefore, File Gateway plus an S3 lifecycle transition to Glacier Deep Archive is the most cost-effective design.