AWS Outposts extends AWS infrastructure and services to on-premises locations. Running Amazon EMR on Outposts allows for processing data that resides locally while benefiting from the managed services of EMR. This enables compliance with data residency requirements and provides scalability and manageability for analytics.

Option Acombines ECS with Fargate for scalability, RDS for relational data, and SQS for decoupling with message ordering (FIFO queues).

Option Buses SNS, which does not maintain message order.

Option Cis suitable for serverless workflows but not relational data.

Option Drelies on Elastic Beanstalk, which offers less flexibility for scaling.

AWS recommends using anIAM role attached to the EC2 instanceso the application can obtaintemporary credentialsautomatically instead of storing long-term access keys in code or configuration. That directly follows AWS security guidance for workloads running on EC2. The role should grant only the specific S3 permissions the application needs, which satisfies the principle of least privilege. Administrative access is too broad, and IAM users with access keys are less secure because they require credential distribution and rotation. The best-practice design is therefore to attach an IAM role with only the required S3 actions to the instance profile and let the SDK retrieve temporary credentials from the instance metadata service.

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The best solution to query and filter S3 data directly without downloading the full object is to use Amazon Athena.

Amazon Athena is an interactive query service that lets you use SQL to analyze structured, semi-structured, and unstructured data directly in Amazon S3, without needing to move or transform the data.

It supports formats like CSV, JSON, ORC, Parquet, and Avro and integrates with AWS Glue Data Catalog for schema management.

Athena is serverless, meaning there’s no infrastructure to manage, and it ' s billed per query, which keeps it cost-effective.

Option B (EMR) is heavier and requires managing a cluster.

Option C (API Gateway) is not suited for querying S3 datasets.

Option D (ElastiCache) is a memory store, not a query engine.

???? Reference:

What is Amazon Athena?

Spot Instances are the best pricing model because the jobscan tolerate interruptions, and the company wants the most cost-effective option. AWS recommends theprice-capacity-optimizedstrategy for Spot because it selects pools that balancelow pricewithlower interruption risk. Using multiple instance types in the Auto Scaling group also helps the company stay flexible enough to adopt newer generations over time. Reserved Instances do not fit as well because they reduce flexibility and do not align with the requirement to keep shifting toward the latest instance generations each year. Capacity-optimized alone minimizes interruption risk, but AWS recommends price-capacity-optimized when you want both lower interruption rates and better prices. Therefore, Spot with price-capacity-optimized allocation is the strongest answer.

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Option Bis the correct solution because:

AWS Security Token Service (STS)allows the web application to request temporary security credentials that grant access to AWS resources. These temporary credentials are secure and short-lived, reducing the risk of misuse.

Using STS and IAM roles ensures scalability by enabling the application to dynamically assume roles with the required permissions for each AWS service.

Option A:Assigning IAM roles directly to instances is less flexible and would grant the same permissions to all applications on the instance, which is not ideal for a multi-service web application.Option C:AWS IAM Identity Center is used for managing single sign-on (SSO) for workforce users and is not designed for granting programmatic access to web applications.Option D:Storing long-term access keys, even in AWS Systems Manager Parameter Store, is less secure and does not scale well compared to temporary credentials from STS.

AWS Documentation References:

AWS Security Token Service (STS)

IAM Roles for Temporary Credentials

Edge-optimized API Gateway endpoints utilize the Amazon CloudFront global network to decrease latency for clients globally. This setup ensures that the request is routed to the closest edge location, significantly reducing response time and improving performance for worldwide users.

The primary requirements are automatic scaling, resilience to traffic spikes, and guaranteed order durability without losing customer orders. Option D follows a well-established, AWS-recommended decoupled architecture pattern that meets all these requirements.

Using an Application Load Balancer (ALB) provides Layer 7 request routing and distributes incoming traffic across multiple EC2 instances in Auto Scaling groups, allowing the application layer to scale horizontally as traffic increases. This ensures that spikes in web traffic do not overwhelm individual instances.

The critical resilience feature in this design is Amazon SQS, which acts as a durable buffer for unprocessed customer orders. If the application experiences a sudden traffic surge or if downstream processing slows, SQS stores incoming orders reliably until they can be processed. This decoupling prevents request loss and protects the user experience by absorbing load bursts.

Processed orders are stored in Amazon RDS with a Multi-AZ deployment, which provides synchronous replication to a standby instance in another Availability Zone and automatic failover. This ensures high availability and data durability for transactional order data.

The other options misuse services or introduce unnecessary complexity. NAT gateways (Option A) do not manage web traffic or provide resiliency for application workloads. Redshift (Option B) is an analytics data warehouse and not suitable for transactional order processing. Gateway Load Balancer (Option C) is designed for network appliances, not application traffic management or order capture.

Therefore, D is the correct solution because it combines load balancing, auto scaling, message queuing, and highly available databases to deliver a resilient, scalable, and fault-tolerant order processing architecture.

The correct answer isDbecause the company needsshared storagefor Amazon EC2 instances that are deployed acrossmultiple Availability Zones, and the application already relies onLinux file system permissionswithout requiring application code changes.Amazon EFSis a fully managed, elastic, shared file system that supports theNFS protocol, which is commonly used by Linux-based applications. It can be mounted concurrently from multiple EC2 instances across multiple Availability Zones, making it the best fit for this requirement.

Amazon EFS preserves standard file system semantics and POSIX-style permissions, which means the company can continue using familiar Linux file permissions and ownership models. This allows the application to work without code modification. EFS is also highly available and durable because it is designed as a Regional service that stores data redundantly across Availability Zones.

Option A is incorrect because Amazon S3 is object storage, not a native shared POSIX file system. Mounting S3 does not provide the same file system behavior and permissions model required by the application. Option B is incorrect because instance store volumes are ephemeral and tied to individual EC2 instances, so they are not suitable for shared, durable storage across multiple instances. Option C is incorrect because Amazon EBS volumes are block storage volumes that are generally attached to a single instance and are not the best solution for shared multi-AZ file access.

AWS best practices recommendAmazon EFSwhen Linux applications require a shared file system, file permissions, and multi-instance access with minimal operational changes. Therefore,Amazon EFSis the most appropriate solution.

Amazon RDS read replicas provide a way to offload read traffic from the primary database, allowing read-intensive applications to query the replica without impacting the performance of the production (write) database. This is especially effective for workloads that involve frequently changing data but do not benefit from caching, since queries are rarely repeated.

Reference Extract from AWS Documentation / Study Guide:

" Read replicas allow you to elastically scale out beyond the capacity constraints of a single DB instance for read-heavy database workloads. "

Source: AWS Certified Solutions Architect – Official Study Guide, RDS Read Replica section.

To securely migrate an on-premises Oracle database to Amazon Aurora, the following steps are recommended:

Use AWS Schema Conversion Tool (AWS SCT) and AWS Database Migration Service (AWS DMS): AWS SCT helps convert the source database schema to a format compatible with the target database (Aurora). AWS DMS facilitates the actual data migration, ensuring minimal downtime and data integrity.

Use AWS Site-to-Site VPN: Establishing a Site-to-Site VPN connection provides a secure and encrypted tunnel between the on-premises environment and AWS. This ensures that data transferred during the migration is protected against interception and unauthorized access.

IAM Roles for Service Accounts (IRSA): IRSA allows you to associate an IAM role with a Kubernetes service account. This enables pods to assume the IAM role and access AWS resources securely.

Annotating Service Accounts: By annotating Kubernetes service accounts with the ARN of the IAM role, you establish the association required for IRSA.

OIDC Identity Provider: EKS clusters use OpenID Connect (OIDC) to authenticate service accounts. Setting up a trust relationship between the IAM role and the OIDC provider allows the Kubernetes service account to assume the IAM role.

The correct answer isBbecause the company needs tocentrally manage backups across multiple AWS accounts, improvedisaster recovery posture, and protect backups fromaccidental deletion or compromise of an AWS account.AWS Backup policies in AWS Organizationsprovide centralized governance and automation for backup plans across member accounts. By storing copies of backups inadditional AWS accounts, the company gains stronger isolation and protection against account-level compromise.

Cross-account backup copies are especially important when the requirement includes protection from a malicious attack on an AWS account. If backups remain only in the same account, an attacker with sufficient permissions in that account could potentially alter or delete them. Storing backup copies in a separate account provides administrative separation and strengthens recovery options. This is a recognized AWS best practice for improving cyber resilience and recovery assurance.

Option A is incorrect because copying backups to additional Availability Zones within the same account does not address centralized management across Organizations or protect against malicious actions in that account. Option C improves regional resilience but still lacks centralized policy-based management and account isolation. Option D provides centralized policy management and cross-Region resilience, but it does not directly address the requirement to protect against an attack on a single AWS account as effectively ascross-account backup copies.

AWS guidance for enterprise backup strategy emphasizescentralized backup management with AWS Backup and AWS Organizations, pluscross-account copiesfor stronger protection and recovery. Therefore, usingAWS Backup policies in Organizations to store copies in additional AWS accountsis the best solution.

When using an SQS queue as an event source for AWS Lambda, the visibility timeout of the SQS queue plays a critical role in preventing duplicate message processing.

" If your Lambda function doesn ' t process the message and delete it from the queue within the visibility timeout period, the message becomes visible again and can be processed again by the same or another function instance. "

— AWS Lambda with SQS

In this scenario, the third-party API may take up to 60 seconds to respond. Since the Lambda function is configured with a 65-second timeout, the visibility timeout of the queue must be greater than or equal to the maximum function execution time to avoid the same message being reprocessed.

Incorrect Options:

A: Memory allocation doesn’t impact duplicate message handling.

B: Timeout is already sufficient; increasing it further does not solve the core issue.

C: Delivery delay controls initial delivery delay, not reprocessing logic.

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)

Amazon Kinesis Data Streams in on-demand mode is purpose-built for real-time ingestion of streaming data and scales automatically with traffic, which is ideal for fluctuating workloads like clickstream data.

Combined with AWS Lambda, which scales concurrently based on incoming events, this setup ensures efficient, real-time processing with minimal configuration and cost overhead.

Option B involves Firehose, which is not optimal for low-latency processing. Option C is incorrect as Kinesis Video Streams is designed for video data, not clickstream. Option D introduces Flink, which adds unnecessary complexity when Lambda suffices.

Comprehensive and Detailed Step-by-Step Explanation:

The goal is totransfer 500 GB dailyfrom multiple global locationsquicklyintoa single S3 bucketwhile keeping operational complexity low.

Option A:✅

Turn on S3 Transfer Acceleration on the destination S3 bucket. Use multipart uploads to directly upload site data to the destination S3 bucket.

S3 Transfer Acceleration (S3-TA)allowsfasterglobal uploads by routing traffic throughAmazon CloudFront’s globally distributed edge locations.

Multipart uploadsimprove efficiency bybreaking large filesinto smaller parts, transferring them in parallel.

Low operational complexity: No need for additional resources or manual replication.

Why is this best?It ensureshigh-speed transferswhileminimizing complexity.

AWS Budgets is the correct service because it is built to track AWS costs and usage and to take action when thresholds are reached. In this scenario, the company explicitly doesnotwant automatic resource restriction, so the right pattern is to use budget thresholds and define an action path that supportsmanual review. AWS documentation explains that AWS Budgets can monitor costs and trigger budget actions, and it also supports forecast-based alerts, which help identify likely overruns as early as possible. Daily reports alone are slower and less proactive, while automatic restrictions violate the requirement. Service control policies are not the mechanism used to define spending thresholds themselves. A Budgets-based workflow is therefore the cleanest and most appropriate solution. (AWS Documentation)

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The requirement to “have access to the operating system” means the compute layer must be Amazon EC2 (or containers on EC2). Managed runtimes such as Lambda and Fargate do not provide OS-level access.

The requirement for a “low-latency NoSQL database” maps directly to Amazon DynamoDB, which is a fully managed NoSQL key-value and document database that provides single-digit millisecond latency at any scale.

Because the application runs in a private subnet, AWS best practice is to access DynamoDB privately via a VPC endpoint (gateway endpoint for DynamoDB). This avoids traversing the public internet and simplifies security.

An instance profile (EC2 role) is the recommended method to grant EC2 instances permission to access DynamoDB without hardcoding credentials.

Why the other options are not correct:

B: Lambda does not provide OS access, which violates the security requirement.

C: Fargate does not provide OS access, and Aurora PostgreSQL is a relational database, not NoSQL.

D: S3 + Athena is an analytics pattern, not a low-latency NoSQL database solution; query latency is much higher and not suitable for OLTP-style app storage.