DEA-C01 Data Operations and Support Practice Question
A data engineer is designing a data lake on Amazon S3 with sensitive data. The engineer needs to ensure that data at rest is encrypted and that access is logged for compliance. Which TWO actions should the engineer take? (Choose TWO.)
⚠ Common exam trap
Test-takers frequently confuse S3 Block Public Access (a security control) with encryption or logging, or they mistakenly think S3 Select or Transfer Acceleration contribute to compliance requirements, when they are unrelated to data-at-rest encryption and access logging.
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
✓
Enable CloudTrail data events for S3 object-level operations.
Option D is correct because enabling default bucket encryption with SSE-KMS ensures all objects written to the S3 bucket are encrypted at rest using AWS KMS-managed keys, satisfying the data-at-rest encryption requirement. Option C is correct because CloudTrail data events capture object-level S3 operations such as GetObject and PutObject, providing the access logging needed for compliance auditing. Option A is incorrect because S3 Select only filters data at read time and does not provide encryption or access logging. Option B is incorrect because S3 Transfer Acceleration only speeds up uploads and downloads over long distances, not encryption or logging. Option E is incorrect because S3 Block Public Access prevents public exposure but does not encrypt data at rest or log access.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Enable S3 Select to filter data at read time.
Why it's wrong here
S3 Select filters object contents at read time for performance; it neither encrypts data at rest nor writes access logs, so it satisfies neither requirement. It is tempting because it is an S3 data-access feature, and would be correct where the goal was reducing data transferred for query processing.
- ✗
Enable S3 Transfer Acceleration.
Why it's wrong here
Transfer Acceleration speeds uploads over AWS edge locations; it does not encrypt objects at rest or log access requests, so it meets neither requirement. It is tempting because it is an S3 performance feature, and would be correct for geographically distant clients needing faster transfers.
- ✓
Enable CloudTrail data events for S3 object-level operations.
Why this is correct
CloudTrail data events capture object-level S3 operations such as GetObject and PutObject, which management events omit entirely. This satisfies the stem's requirement that access be logged for compliance, since only data events record who read or wrote the sensitive objects.
- ✓
Enable default encryption on the S3 bucket using SSE-KMS.
Why this is correct
SSE-KMS encrypts every object at rest using AWS KMS keys, satisfying the encryption requirement while supporting key rotation and audit trails via CloudTrail. Unlike SSE-S3, it gives granular key policies and per-key usage logging, which compliance frameworks demand. This directly meets the stem's data-at-rest encryption constraint for sensitive S3 data.
- ✗
Enable S3 Block Public Access on the account.
Why it's wrong here
Block Public Access prevents public exposure but neither encrypts objects at rest nor records access requests, so both stated requirements remain unmet. It is tempting because it is a core S3 security control, and would be correct where the requirement was preventing accidental public exposure.
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
One of 1,321 original DEA-C01 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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.