SOA-C02 Cost and Performance Optimization Practice Question
A SysOps administrator wants to identify underutilized Amazon EC2 instances that could be downsized to reduce costs. The administrator needs a tool that provides recommendations based on historical utilization data. Which AWS service should the administrator use?
⚠ Common exam trap
Test-takers frequently confuse AWS Trusted Advisor's idle instance check with Compute Optimizer's detailed, ML-driven downsizing recommendations, but Trusted Advisor only flags instances with low average CPU utilization (e.g., below 10%) without considering memory, network, or storage patterns.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
AWS Compute Optimizer
AWS Compute Optimizer is the correct service because it analyzes historical utilization metrics (CPU, memory, network, and storage) for EC2 instances and generates specific downsizing recommendations to reduce cost without sacrificing performance. It uses machine learning to identify underutilized resources and provides actionable guidance, making it the ideal tool for this use case.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
AWS Trusted Advisor
Why it's wrong here
AWS Trusted Advisor does surface cost optimization checks that scan for idle or underutilized EC2 instances, but its guidance is coarse-grained and general. It lacks the machine-learning-driven, instance-level right-sizing recommendations that assess historical utilization patterns and project savings. Trusted Advisor is more of a holistic best-practice auditor, whereas determining underutilized instances with precise size changes requires a dedicated service.
- ✓
AWS Compute Optimizer
Why this is correct
AWS Compute Optimizer is the correct service because it uses machine learning to analyze historical CloudWatch metrics—CPU, memory, network, and storage—and generates specific, right-sized recommendations for EC2 instances. It can suggest downsizing an instance family or size, or even terminating instances that are consistently underutilized, while estimating the monthly cost savings and performance risk. This granular, workload-specific analysis directly addresses the goal of identifying underutilized Amazon EC2 resources.
- ✗
AWS Cost Explorer
Why it's wrong here
AWS Cost Explorer is primarily a cost and usage analysis tool that offers interactive dashboards, filtering, and grouping to help you understand your AWS spend over time. While it can show you how much you are spending on each instance or tag, it does not evaluate utilization metrics like CPU or memory to determine whether an instance is underutilized. Cost Explorer provides no right-sizing recommendations, so it cannot identify which specific EC2 instances should be downsized or terminated.
- ✗
AWS Budgets
Why it's wrong here
AWS Budgets is designed for cost governance—it lets you set custom cost or usage budgets and receive alerts when actual or forecasted spending exceeds your thresholds. It does not analyze EC2 utilization data, nor does it suggest any instance resizing or terminations. Budgets would only notify you if you are over-spending, not if an instance is idle or oversized, making it irrelevant for identifying underutilized Amazon EC2 instances.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
Go deeper
Related to this question
About these practice questions
Courseiva writes every SOA-C02 question from scratch — 1,169 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
Same concept, more angles
1 more way this is tested on SOA-C02
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A SysOps administrator wants to identify Amazon EC2 instances that are underutilized to reduce costs. The administrator needs recommendations for rightsizing instances based on historical CPU and memory usage. Which AWS service provides these recommendations?
easy- A.AWS Cost Explorer
- B.AWS Trusted Advisor
- ✓ C.AWS Compute Optimizer
- D.AWS CloudTrail
Why C: AWS Compute Optimizer is the correct service because it analyzes historical utilization metrics (CPU, memory, I/O, and network throughput) from Amazon CloudWatch and generates rightsizing recommendations for EC2 instances. It uses machine learning to identify underutilized instances and suggests instance types that better match workload requirements, directly addressing the need to reduce costs through rightsizing.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SOA-C02 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SOA-C02 exam.