A startup runs a mix of workloads using both EC2 instances and AWS Lambda functions. Over the next 12 months, the team expects the overall level of compute usage to be fairly steady, but they may change EC2 instance types for performance tuning and they may add or remove Lambda functions. They want the lowest-cost commitment that will discount *both* EC2 and Lambda usage without requiring them to commit to a specific EC2 instance family (or a fixed instance type). Which AWS option best meets this requirement?

Purchase an EC2 Instance Reserved Instance for the current instance family only, and rely on On-Demand pricing for Lambda and any future EC2 types.

EC2 Instance Reserved Instances discount EC2 usage for a specific instance family (and matching attributes). They do not apply to AWS Lambda, so Lambda usage would stay On-Demand. They also reduce flexibility if the team later changes instance families/types.

Purchase a Standard Reserved Instance for a specific Region and use it only to reduce network egress/transfer charges.

Reserved Instances discounts EC2 instance usage (compute). They do not directly discount network egress or S3/other transfer charges. This choice also does not cover Lambda discounts.

Use EC2 Spot for EC2 workloads and keep Lambda on-demand, because Spot will automatically discount Lambda too.

EC2 Spot pricing applies to EC2 capacity only and does not automatically extend to AWS Lambda. Spot also introduces interruption risk for EC2, which may not align with the goal of a steady discount-based commitment across mixed EC2 and Lambda compute usage.

What does this SAA-C03 question test?

Read the scenario before looking for a memorised answer.

What is the correct answer to this question?

The correct answer is: Purchase a Compute Savings Plan with a 1-year term for the expected average hourly spend across both EC2 and Lambda. — A 1-year Compute Savings Plan best matches the requirements. Compute Savings Plans discount eligible compute usage across EC2 and AWS Lambda based on a committed amount rather than binding you to a specific EC2 instance family/type. That preserves flexibility to change EC2 instance types and to add/remove Lambda functions while still lowering compute costs with a steady commitment. EC2 Instance Reserved Instances are EC2-only and are instance-family/type bound, so they do not discount Lambda and they restrict flexibility. Reserved Instances also do not discount generic transfer/network egress charges. Spot discounts EC2 only and does not apply to Lambda, plus it can interrupt EC2 capacity, which is not guaranteed to meet the team’s steady-discount objective across both workload types.

What should I do if I get this SAA-C03 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.