DEA-C01 Data Operations and Support Practice Question
A data engineer needs to ensure that data in an Amazon S3 bucket is not publicly accessible. Which TWO measures should the engineer implement? (Choose TWO.)
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
✓
Attach a bucket policy that denies access to 'Principal': '*' unless specific conditions are met.
To prevent public access to an S3 bucket, you can use bucket policies that explicitly deny access to anonymous principals (option A) or enable S3 Block Public Access settings (option C). Option B is incorrect because lifecycle policies manage object retention and deletion, not access control. Option D is incorrect because versioning protects against accidental deletion/overwrites but does not control access. Option E is incorrect because default encryption secures data at rest but does not restrict public 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.
- ✓
Attach a bucket policy that denies access to 'Principal': '*' unless specific conditions are met.
Why this is correct
A bucket policy can deny all public access.
- ✗
Create a lifecycle policy to delete objects after 30 days.
Why it's wrong here
Lifecycle policies manage object expiration, not access control.
- ✓
Enable S3 Block Public Access settings on the bucket.
Why this is correct
This setting explicitly blocks any public access.
- ✗
Enable S3 Versioning on the bucket.
Why it's wrong here
Versioning protects against overwrites, not public access.
- ✗
Enable default encryption on the bucket.
Why it's wrong here
Encryption protects data at rest but does not affect public access.
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
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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.