Amazon Web Services SAA-C03 Exam With Confidence Using Practice Dumps

AWS Step Functions can orchestrate Lambda executions without modifying the Lambda code, and the Map state is designed to run a Lambda function once per item in a list—perfect for activating many devices in parallel or controlled batches.

This eliminates the loop inside the Retrieve function and prevents timeouts.

EventBridge (Option A) only changes the schedule. DynamoDB Streams (Option B) is unrelated to the activation workflow. EC2 (Option D) increases operational overhead.

The best practice to securely provide short-term access to AWS resources, such as Amazon S3, without using long-term credentials, is to use AWS Security Token Service (STS). According to the AWS IAM Best Practices and the Security Pillar of the AWS Well-Architected Framework, temporary credentials should always be used over long-term credentials when possible.

From AWS IAM Documentation:

“Use temporary credentials (IAM roles and AWS STS) instead of long-term access keys. Temporary security credentials are short-term, automatically expire, and are retrieved using AWS STS.”

(Source: IAM Best Practices – IAM User Guide)

Option D outlines the use of a trust relationship and assume-role mechanism via AWS STS. This allows the on-premises application to request temporary, scoped-down credentials to upload files to S3 securely. This approach is:

Secure – Uses short-lived credentials with least privilege

Scalable – No need for EC2 or VPN tunnels

Low Operational Overhead – No infrastructure to maintain

AWS-Recommended – Aligned with security best practices

In contrast:

Option A uses long-term credentials, which is a security risk.

Option B requires additional infrastructure (EC2, VPN), increasing complexity and cost.

Option C relies on IP-based access, which is insecure and not a form of identity-based authentication.

The correct answer isCbecause the existing application usesNFS storagefor an image cache that isa few terabytes in size, and the company wants themost cost-effective cloud alternative.Amazon EFS One Zoneis a managed file storage service that supports theNFS protocol, which allows the application to continue using a familiar file-based interface with minimal architectural change. Because this is acache, not primary durable data, storing it in aOne Zonefile system is a cost-optimized choice compared with a Regional EFS deployment.

Amazon EFS is designed for shared file storage and can scale to multiple terabytes automatically. It avoids the operational overhead of managing EC2 instances and local disks for cache storage. It is also better aligned than object storage for workloads that already expect direct NFS semantics. The application can mount the EFS file system and use it as the cache backend without redesigning around object APIs or in-memory caching models.

Option A is incorrect becauseElastiCache Memcachedis an in-memory cache and is typically much more expensive for multi-terabyte cache data than file storage. Option B is incorrect because using EC2 instance store volumes creates significant management overhead and the cache would be lost whenever instances are terminated or replaced. Option D is incorrect becauseAmazon S3 Express One Zoneis object storage, not NFS storage, and would require application redesign and additional metadata management in DynamoDB.

AWS storage guidance recommends matching file-based workloads to managed file services. For a largeNFS-based cache,Amazon EFS One Zoneis the most cost-effective and operationally simple solution.