SAA-C03 Design Cost-Optimized Architectures Practice Test 6 — 15 Questions

Question 1

A company is using AWS for big data analytics and wants to optimize costs for its data processing pipeline. Which three design choices will help achieve this goal? (Choose three.)

Accepted Answer

Use Amazon EMR with Spot Instances for task nodes to reduce compute costs for fault-tolerant jobs.. Using Amazon EMR with Spot Instances for task nodes is correct because task nodes are typically used for fault-tolerant, stateless processing in EMR clusters. Spot Instances offer significant cost savings (up to 90% compared to On-Demand) and can be interrupted, but since task nodes can be replaced without affecting job completion, this is a cost-optimized design for big data pipelines. Amazon S3 Select is correct because it allows you to retrieve only a subset of data from an object (e.g., specific columns or rows) using SQL expressions, reducing the amount of data transferred to your processing application and lowering data transfer and processing costs. Using AWS Glue with a scheduled crawler and choosing a lower number of DPUs for smaller jobs is correct because DPUs (Data Processing Units) are the billing unit for AWS Glue jobs; selecting a lower DPU count for jobs that do not require high parallelism directly reduces costs.

Answer

Store all intermediate data on Amazon EBS io2 Block Express volumes for high performance.

Answer

Store all data in Amazon Redshift Spectrum external tables to avoid loading data into Redshift clusters.

Answer

Provision a fixed number of EC2 instances for processing to avoid scaling delays.

Question 2

A company is running a stateful web application on EC2 instances that processes user uploads. The architecture currently uses a Multi-AZ deployment for high availability. Which three cost-optimization strategies can be applied without sacrificing high availability? (Choose three.)

Accepted Answer

Use EC2 Auto Scaling with a mixed instances policy that includes Spot Instances for the stateless web tier, while using On-Demand for the stateful tier.. Storing uploaded files in Amazon S3 and using S3 Transfer Acceleration for uploads removes the need for local storage on EC2 instances, reducing storage costs and eliminating the cost of managing EBS volumes. This strategy does not affect high availability because S3 is inherently highly available and durable across multiple Availability Zones. Transfer Acceleration optimizes upload speed over the public internet without impacting the availability of the application.

Answer

Implement a NAT Gateway in each Availability Zone for outbound traffic to reduce data transfer costs.

Answer

Replace Multi-AZ EC2 with a single-AZ deployment to reduce data transfer costs.

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Use an Amazon ElastiCache cluster in a single Availability Zone to reduce costs.

Question 3

A company is designing a cost-optimized serverless architecture using AWS Lambda for a data processing workload. The workload runs multiple times per day and processes files up to 500 MB. Which three design decisions will help minimize costs? (Choose three.)

Accepted Answer

Optimize the Lambda function code to reduce execution duration, as cost is based on compute time.. Optimizing the Lambda function code to reduce execution duration directly lowers costs because AWS Lambda pricing is based on the number of requests and the duration of code execution, measured in GB-seconds. By writing efficient code, you reduce the compute time, which minimizes the billable GB-seconds. Storing processed output in S3 Standard-IA is cost-effective for infrequently accessed data, as it offers lower storage costs than S3 Standard while still providing high durability and availability. Using S3 batch operations to invoke Lambda functions in parallel reduces the overall processing time by distributing the workload across multiple concurrent invocations, which can lower the total compute duration and thus the cost.

Answer

Deploy Lambda functions in multiple Regions to reduce latency for global users.

Answer

Use Lambda Provisioned Concurrency to ensure zero cold starts, improving performance.

Answer

Allocate the maximum memory (10,240 MB) to each Lambda function to reduce execution time.

Question 4

A data analytics company stores large datasets in Amazon S3. The data is accessed frequently for the first 30 days, then accessed rarely but needs to be retrievable within 1 hour for compliance purposes for up to 3 years. After 3 years, the data must be archived for 7 years with retrieval times acceptable up to 12 hours. Which three of the following strategies would optimize storage costs? (Choose three.)

Accepted Answer

Use S3 Intelligent-Tiering for automatic cost savings based on access patterns.. The optimal cost-optimization strategy involves using S3 Intelligent-Tiering to automatically move objects between access tiers based on changing patterns, saving costs without manual lifecycle rules. Additionally, transition objects to S3 Standard-IA after 30 days to match reduced access frequency, and use a lifecycle policy to move objects to S3 Glacier Deep Archive after 3 years to meet the 12-hour retrieval requirement for the final 7-year archive. These three strategies optimize storage costs effectively.

Answer

Store all data in S3 One Zone-IA for the first 30 days to save on storage costs.

Answer

Transition data to S3 Glacier Deep Archive immediately after upload.

Question 5

Order the steps for setting up an Application Load Balancer with an EC2 target group.

Accepted Answer

Step 1: Create Application Load Balancer; Step 2: Create target group; Step 3: Configure health checks; Step 4: Register EC2 instances; Step 5: Test the load balancer. The correct sequence for setting up an Application Load Balancer with an EC2 target group is: first create the ALB to define listeners, then create a target group to handle traffic routing, configure health checks to monitor instance health, register EC2 instances into the target group, and finally test the load balancer to ensure proper operation. This order ensures all dependencies are met and follows AWS best practices.

Answer

Step 1: Create target group; Step 2: Create Application Load Balancer; Step 3: Configure health checks; Step 4: Register EC2 instances; Step 5: Test the load balancer

Answer

Step 1: Create Application Load Balancer; Step 2: Register EC2 instances; Step 3: Create target group; Step 4: Configure health checks; Step 5: Test the load balancer

Answer

Step 1: Create Application Load Balancer; Step 2: Configure health checks; Step 3: Create target group; Step 4: Register EC2 instances; Step 5: Test the load balancer

Question 6

Order the steps to set up an Amazon CloudFront distribution with an S3 origin.

Accepted Answer

Step 1: Create an S3 bucket. Step 2: Create a CloudFront distribution. Step 3: Configure cache settings. Step 4: Create an Origin Access Identity (OAI). Step 5: Update the S3 bucket policy.. S3 bucket first, then CloudFront distribution, cache settings, OAI creation, and bucket policy update.

Answer

Step 1: Create an S3 bucket. Step 2: Create a CloudFront distribution. Step 3: Create an Origin Access Identity (OAI). Step 4: Configure cache settings. Step 5: Update the S3 bucket policy.

Answer

Step 1: Create an S3 bucket. Step 2: Create an Origin Access Identity (OAI). Step 3: Update the S3 bucket policy. Step 4: Create a CloudFront distribution. Step 5: Configure cache settings.

Answer

Step 1: Create a CloudFront distribution. Step 2: Create an S3 bucket. Step 3: Configure cache settings. Step 4: Create an Origin Access Identity (OAI). Step 5: Update the S3 bucket policy.

Question 7

A data analytics team runs an Amazon RDS for PostgreSQL database that supports a nightly ETL job. The job performs large sequential reads across several tables and runs for about three hours each night. During the rest of the day, the database serves a small number of users with light, random read/write queries. The database currently uses a General Purpose SSD (gp3) volume with 3,000 provisioned IOPS and 500 GiB of storage. The team wants to reduce storage cost without degrading the nightly ETL performance. What should a solutions architect recommend?

Accepted Answer

Change the storage type to Throughput Optimized HDD (st1) and keep the same allocated storage.. The nightly ETL performs large sequential reads, which is exactly the access pattern Throughput Optimized HDD (st1) is built for, and st1 is cheaper per GiB than gp3. Because the daytime workload is light and random, the latency trade-off is acceptable. This lowers storage cost while preserving the throughput the ETL needs.

Answer

Migrate the RDS instance to a Magnetic (standard) storage volume and increase the allocated storage size.

Answer

Move the tables to an Amazon S3 bucket and query them with Amazon Athena instead of RDS.

Answer

Keep the gp3 volume but purchase a Reserved Instance for the RDS instance to lower the compute cost.

Question 8

A financial services firm stores 400 TB of regulatory documents in Amazon S3 Standard. Auditors require that documents remain retrievable within milliseconds for the first 90 days, after which they are accessed only during annual audits and must be retained for 7 years. The firm wants to minimize storage cost without changing the application's read path. Which solution meets these requirements?

Accepted Answer

Create an S3 Lifecycle rule that transitions objects to S3 Glacier Instant Retrieval after 90 days and expires them after 7 years.. The access pattern is known and stable: millisecond retrieval for 90 days, then rare annual access for seven years. S3 Glacier Instant Retrieval matches that pattern exactly, offering low-cost archive storage with millisecond reads and a 90-day minimum duration that aligns with the transition. A lifecycle rule automates the transition and expiration, and the application read path is unchanged because the objects remain in the same bucket.

Answer

Create an S3 Lifecycle rule that transitions objects to S3 One Zone-IA after 90 days and expires them after 7 years.

Answer

Enable S3 Intelligent-Tiering and configure an archive access tier after 90 days.

Answer

Create an S3 Lifecycle rule that transitions objects to S3 Glacier Deep Archive after 90 days and expires them after 7 years.

Question 9

A financial services company runs a steady-state production web application on a fleet of 40 EC2 instances in us-east-1. The workload has run continuously for over two years and is expected to continue for at least three more years. The company requires the lowest possible compute cost and can commit to a long-term spend. Which EC2 purchasing strategy should the solutions architect recommend?

Accepted Answer

Purchase a 3-year All Upfront Compute Savings Plan covering the expected hourly compute usage.. A steady, multi-year, always-on workload is the ideal candidate for a long-term commitment discount, and a 3-year All Upfront Compute Savings Plan delivers the maximum discount while preserving flexibility across instance families and regions. Reserved Instances and On-Demand cost more or constrain flexibility, and Spot cannot guarantee continuous availability for a production financial application.

Answer

Use On-Demand Instances and apply AWS Cost Explorer rightsizing recommendations each month.

Answer

Run all instances as Spot Instances with a capacity-optimized allocation strategy.

Answer

Purchase 3-year Standard Reserved Instances for each of the 40 instances.

Question 10

A financial services company runs a containerized trading analytics platform on Amazon EKS. The workload is latency-sensitive and must run continuously with predictable capacity. The company has committed to a three-year horizon and wants the lowest possible compute cost. The platform uses a mix of On-Demand and Spot capacity today, but Spot interruptions have caused missed SLAs. A solutions architect must recommend a purchasing strategy for the EKS worker nodes. Which combination of actions will meet these requirements MOST cost-effectively?

Accepted Answer

Purchase a three-year EC2 Instance Savings Plan for the specific instance family and Region, and run all worker nodes on On-Demand capacity.. The platform runs continuously with predictable capacity and a three-year commitment, which is the ideal profile for an EC2 Instance Savings Plan that locks in a specific instance family and Region for the deepest discount. Removing Spot capacity eliminates the interruptions that broke the SLAs, so the combination delivers the lowest reliable compute cost.

Answer

Purchase a three-year Compute Savings Plan and continue using Spot capacity for a portion of the worker nodes.

Answer

Use EC2 Instance Savings Plans for a three-year term with the Compute Savings Plans commitment level, and remove all Spot capacity.

Answer

Reserve the worker nodes with a three-year Convertible Reserved Instance and keep a small Spot pool for burst capacity.

Question 11

A financial services firm stores quarterly regulatory reports in an S3 bucket. Each report is accessed frequently for the first 60 days after publication, then almost never accessed again, but it must remain individually retrievable within milliseconds for seven years. Retrieval latency above a few hundred milliseconds would break the downstream audit tool. Which lifecycle configuration meets these requirements at the lowest cost?

Accepted Answer

Transition objects to S3 Glacier Instant Retrieval after 60 days and expire them after 2555 days. The decisive constraint is millisecond retrieval for the full seven years, which eliminates the archival classes that require restoration. Among classes that remain instantly readable, Glacier Instant Retrieval offers the lowest storage price for data accessed only a few times a year, so transitioning after the 60-day hot window and expiring at 2555 days is the cheapest compliant design.

Answer

Transition objects to S3 One Zone-IA after 60 days and expire them after 2555 days

Answer

Transition objects to S3 Glacier Deep Archive after 60 days and expire them after 2555 days

Answer

Keep objects in S3 Standard for 60 days, then transition to S3 Intelligent-Tiering and expire after 2555 days

Question 12

A financial services company stores monthly regulatory reports in an Amazon S3 bucket. The reports are accessed frequently for the first 90 days after creation, then almost never accessed, but they must be retained for 7 years to meet compliance requirements. The compliance team requires that the reports remain immediately retrievable within milliseconds throughout the entire retention period. The company wants to minimize storage costs. Which S3 lifecycle configuration will meet these requirements MOST cost-effectively?

Accepted Answer

Transition objects to S3 Standard-IA after 30 days, then to S3 Glacier Instant Retrieval after 90 days, and expire them after 7 years.. The requirements combine long-term retention with millisecond retrieval, which points to S3 Glacier Instant Retrieval as the archival class. A lifecycle that moves data from S3 Standard to S3 Standard-IA and then to Glacier Instant Retrieval balances cost and access. Classes with slower retrieval or single-AZ durability do not meet the immediate-access and compliance needs.

Answer

Transition objects to S3 Standard-IA after 30 days, then to S3 Glacier Deep Archive after 90 days, and expire them after 7 years.

Answer

Transition objects to S3 One Zone-IA after 30 days, then to S3 Glacier Instant Retrieval after 90 days, and expire them after 7 years.

Answer

Keep objects in S3 Standard for 90 days, then transition directly to S3 Glacier Flexible Retrieval for the remainder of the retention period.

Question 13

A small startup runs a nightly batch job on a single Amazon EC2 instance. The job processes files for about two hours, then the instance sits idle for the remaining 22 hours. The team wants the lowest possible cost and can tolerate the instance being unavailable during the day. The job can be restarted if interrupted. What is the MOST cost-effective approach?

Accepted Answer

Run the job on a Spot Instance and let the job restart from the beginning if the instance is reclaimed.. The workload is short, scheduled, and interruption-tolerant, which is exactly the profile Spot Instances are designed for. Spot capacity is priced far below On-Demand, and the job can restart if the instance is reclaimed. Running the instance only during the two-hour processing window keeps billed hours low, so combining a short duty cycle with Spot pricing produces the lowest overall cost.

Answer

Use an On-Demand instance and stop it when the job completes, starting it again before the next run.

Answer

Migrate the batch job to a Dedicated Host to get consistent performance at a lower price.

Answer

Purchase a 3-year All Upfront Reserved Instance for the instance and leave it running continuously.

Question 14

A financial analytics firm runs a daily risk simulation on a fleet of 40 EC2 instances. The simulation starts at 02:00 and must finish by 06:00. The instances are used only during this 4-hour window and are stopped afterward. The firm wants to minimize compute costs while ensuring the instances are available at the exact start time. Which solution meets these requirements MOST cost-effectively?

Accepted Answer

Create a recurring schedule using AWS Instance Scheduler to start and stop 40 On-Demand Instances, and purchase a 1-year Compute Savings Plan.. The workload is predictable and runs only 4 hours per day, so cost optimization requires both automated start/stop and a commitment-based discount that applies only when instances run. A Compute Savings Plan provides a lower hourly rate for the On-Demand usage that actually occurs, while Instance Scheduler prevents charges during idle hours. Reserved Instances and On-Demand without a plan would cost more for this intermittent pattern.

Answer

Use 40 Spot Instances with a persistent request and a capacity-optimized allocation strategy.

Answer

Purchase 40 Standard Reserved Instances for a 1-year term with no upfront payment.

Answer

Purchase 40 On-Demand Instances and use AWS Instance Scheduler to stop them at 06:00.

Question 15

A company is building a data lake in Amazon S3 that receives continuous uploads from many applications. The data is queried frequently for the first 60 days, then accessed only a few times per year, and finally must be retained for seven years for regulatory compliance. The company wants to minimize storage cost without losing the ability to retrieve data when needed. Which two actions should the company take? (Choose two.)

Accepted Answer

Configure an S3 Lifecycle rule to transition objects to S3 Glacier Deep Archive after one year.. Combining a transition to S3 Standard-IA after the active 60-day window with a later transition to S3 Glacier Deep Archive matches each lifecycle stage to the cheapest class that still meets its access needs. Standard-IA preserves fast access during occasional-use years, and Deep Archive minimizes cost during the long regulatory retention tail, keeping the data durable and retrievable.

Answer

Enable S3 Cross-Region Replication to a second Region for all objects.

Answer

Enable S3 Transfer Acceleration on the bucket to reduce upload costs.

Answer

Convert the bucket to S3 One Zone-IA for the entire seven-year period.