SOA-C02 Cost and Performance Optimization Practice Question

A company stores log files in Amazon S3. The logs are accessed frequently for the first 30 days, then rarely after that. The company wants to automatically transition objects to a lower-cost storage class after 30 days. Which S3 feature should be configured?

⚠ Common exam trap

Many candidates confuse S3 Versioning or Object Lock as tools for cost optimization, but they are governance features, not lifecycle management features, and do not automate storage class transitions.

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

✓

S3 Lifecycle rule

An S3 Lifecycle rule is the correct feature because it allows you to define a transition action that automatically moves objects from a higher-cost storage class (e.g., S3 Standard) to a lower-cost storage class (e.g., S3 Standard-IA or S3 Glacier) after a specified number of days. This directly meets the requirement to transition logs after 30 days without manual intervention, optimizing storage costs based on access patterns.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
S3 Lifecycle rule
Why this is correct
S3 Lifecycle rules automatically transition objects to lower-cost storage classes (e.g., from S3 Standard to S3 Standard-IA or S3 Glacier Deep Archive) based on age or other criteria. For logs that are accessed infrequently after 30 days and must be retained for years, a lifecycle rule is the most cost-effective way to automate the transition and expiration of objects while still meeting retention requirements.
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S3 Versioning
Why it's wrong here
S3 Versioning maintains multiple versions of the same object, protecting against accidental overwrites or deletions by keeping every version. However, it does not change the storage class of objects and does not provide any cost optimization for infrequently accessed logs. In fact, versioning can increase storage costs because every version consumes storage, so it is not the correct mechanism for managing the lifecycle of log files.
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S3 Transfer Acceleration
Why it's wrong here
S3 Transfer Acceleration uses AWS edge locations to route uploads over an optimized network path, speeding up data ingestion into S3. This feature is purely for improving upload performance and involves additional per-GB transfer charges; it has no effect on how objects are stored, transitioned, or retained after upload. Therefore, it cannot address the need for cost-effective long-term storage of log files.
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S3 Object Lock
Why it's wrong here
S3 Object Lock implements a WORM (Write Once Read Many) model by enabling retention periods or legal holds that prevent objects from being deleted or overwritten. While this can help meet compliance requirements for preserving logs, it does not manage storage class transitions or reduce storage costs. Object Lock alone would leave log files in their original storage class, so it is not a cost-optimization solution.

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

SOA-C02 Cost and Performance Optimization Practice Question

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

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