DEA-C01 Data Store Management Practice Question
A data engineer is designing a data lake on Amazon S3 and needs to ensure that objects are automatically encrypted at rest using server-side encryption with AWS KMS. Which bucket policy statement achieves this?
⚠ Common exam trap
Test-takers frequently confuse the encryption header values (`aws:kms` vs `AES256`) and mistakenly choose an option that enforces SSE-S3 (AES256) instead of SSE-KMS, or they pick a Deny statement that only checks for the presence of the header without validating its specific value.
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
✓
Deny PutObject requests where the x-amz-server-side-encryption header is not set to aws:kms.
It enforces server-side encryption with AWS KMS (SSE-KMS) by denying any PutObject request that does not include the `x-amz-server-side-encryption` header set to `aws:kms`. This bucket policy ensures that all objects written to the S3 bucket are automatically encrypted at rest using AWS KMS, meeting the requirement for mandatory encryption with a specific key management service.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Deny PutObject requests where the x-amz-server-side-encryption header is not set to aws:kms.
Why this is correct
Enforces SSE-KMS encryption.
- ✗
Deny PutObject requests that do not include the x-amz-server-side-encryption header.
Why it's wrong here
Does not enforce KMS specifically.
- ✗
Deny PutObject requests where the x-amz-server-side-encryption header is not set to AES256.
Why it's wrong here
This enforces SSE-S3, not KMS.
- ✗
Allow PutObject requests only if the x-amz-server-side-encryption header is set to AES256.
Why it's wrong here
This enforces SSE-S3, not KMS.
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
This DEA-C01 question is part of Courseiva's 1,711-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DEA-C01 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 DEA-C01 exam.